View:
Download DOC
Download PDF
Download XLS

QuickLinks -- Click here to rapidly navigate through this document

 

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549


SCHEDULE TO

TENDER OFFER STATEMENT UNDER SECTION 14(D)(1) OR 13(E)(1)
OF THE SECURITIES EXCHANGE ACT OF 1934

FORTY SEVEN, INC.
(Name of Subject Company (Issuer))

TORO MERGER SUB, INC.
a wholly owned subsidiary of

GILEAD SCIENCES, INC.
(Names of Filing Persons (Offeror))

Common Stock, Par Value $0.0001 Per Share
(Title of Class of Securities)

34983P104
(Cusip Number of Class of Securities)

Brett A. Pletcher, Esq.
Executive Vice President, Corporate Affairs, General Counsel and Corporate Secretary
Gilead Sciences, Inc.
333 Lakeside Drive
Foster City, CA 94404
650-574-3000
(Name, Address and Telephone Number of Person Authorized to
Receive Notices and Communications on Behalf of Filing Persons)

Copies to:

Stephen F. Arcano
Skadden, Arps, Slate, Meagher & Flom LLP
One Manhattan West
New York, NY 10001
(212) 735-3542		   Graham Robinson
Skadden, Arps, Slate, Meagher & Flom LLP
500 Boylston Street
Boston, MA 02116
(617) 573-4850

CALCULATION OF FILING FEE

 
Transaction Valuation*
   Amount of Filing Fee**
 
$4,949,381,117.36   $642,429.67
 
*
Estimated for purposes of calculating the filing fee only. The transaction valuation was calculated as the sum of (i) 48,151,481 outstanding shares of common stock, par value $0.0001 per share (the "Shares"), of Forty Seven, Inc. ("Forty Seven") multiplied by $95.50, (ii) 1,341,064 Shares issuable pursuant to outstanding stock options that have vested (or are anticipated to vest prior to the completion of the transaction) multiplied by $95.50, and (iii) 2,924,066 Shares issuable pursuant to outstanding unvested stock options multiplied by $76.21 (which is $95.50 minus the weighted average exercise price for such options of $19.29 per share). The calculation of the filing fee is based on information provided by Forty Seven as of February 29, 2020.

**
The filing fee was calculated in accordance with Rule 0-11 under the Securities Exchange Act of 1934, as amended, and Fee Rate Advisory No. 1 for Fiscal Year 2020, issued August 23, 2019, by multiplying the transaction value by 0.0001298
o
Check box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.
Amount Previously Paid:   None   Filing Party:   Not applicable
Form or Registration No.:   Not applicable   Date Filed:   Not applicable
o
Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

ý
third-party tender offer subject to Rule 14d-1.

o
issuer tender offer subject to Rule 13e-4.

o
going-private transaction subject to Rule 13e-3.

o
amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer. o

   

        This Tender Offer Statement on Schedule TO (this "Schedule TO") relates to the offer by Toro Merger Sub, Inc., a Delaware corporation ("Purchaser"), and Gilead Sciences, Inc., a Delaware corporation ("Parent"), to purchase all outstanding shares of common stock, $0.0001 par value per share ("Shares"), of Forty Seven, Inc., a Delaware corporation ("Forty Seven"), at a price of $95.50 per Share, net to the holder in cash, without interest and subject to any withholding of taxes, upon the terms and subject to the conditions described in the Offer to Purchase dated March 10, 2020 (together with any amendments or supplements thereto, the "Offer to Purchase") and in the accompanying Letter of Transmittal (together with any amendments or supplements thereto and with the Offer to Purchase, the "Offer"), which are annexed to and filed with this Schedule TO as Exhibits (a)(1)(A) and (a)(1)(B), respectively. Purchaser is a wholly owned subsidiary of Parent. This Schedule TO is being filed on behalf of Parent and Purchaser. Unless otherwise indicated, references to sections in this Schedule TO are references to sections of the Offer to Purchase. A copy of the Agreement and Plan of Merger, dated as of March 1, 2020, among Forty Seven, Parent and Purchaser is attached as Exhibit (d)(1) hereto and incorporated herein by reference with respect to Items 4 through 11 of this Schedule TO.

ITEM 1.    SUMMARY TERM SHEET.

        The information set forth in the section of the Offer to Purchase titled "Summary Term Sheet" is incorporated herein by reference.

ITEM 2.    SUBJECT COMPANY INFORMATION.

        (a)   The subject company and the issuer of the securities subject to the Offer is Forty Seven, Inc. Its principal executive office is located at 1490 O'Brien Drive, Suite A, Menlo Park, CA 94025, and its telephone number is (650) 352-4150.

        (b)   This Schedule TO relates to Shares. According to Forty Seven, as of the close of business on February 29, 2020, there were (i) 48,151,481 Shares issued and outstanding and (ii) 4,265,130 Shares subject to issuance pursuant to outstanding options to acquire Shares.

        (c)   The information concerning the principal market, if any, in which the Shares are traded and certain high and low sales prices for the Shares in the principal market in which the Shares are traded set forth in Section 6—"Price Range of Shares; Dividends" of the Offer to Purchase is incorporated herein by reference.

ITEM 3.    IDENTITY AND BACKGROUND OF FILING PERSON.

        (a) - (c) The filing companies of this Schedule TO are (i) Parent and (ii) Purchaser. Each of Purchaser's and Parent's principal executive office is located at c/o Gilead Sciences, Inc., 333 Lakeside Drive, Foster City, CA 94404, and the telephone number of each is (650) 574-3000. The information regarding Purchaser and Parent set forth in Section 9—"Certain Information Concerning Parent and Purchaser" and Schedule A of the Offer to Purchase is incorporated herein by reference.

ITEM 4.    TERMS OF THE TRANSACTION.

        The information set forth in the Offer to Purchase is incorporated herein by reference.

ITEM 5.    PAST CONTACTS, TRANSACTIONS, NEGOTIATIONS AND AGREEMENTS.

        (a), (b) The information set forth in Section 8—"Certain Information Concerning Forty Seven", Section 9—"Certain Information Concerning Parent and Purchaser", Section 10—"Background of the Offer; Contacts with Forty Seven", Section 11—"Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements" and Schedule A of the Offer to Purchase is incorporated herein by reference.

ITEM 6.    PURPOSES OF THE TRANSACTION AND PLANS OR PROPOSALS.

        (a), (c)(1) - (7) The information set forth in the sections of the Offer to Purchase titled "Summary Term Sheet" and "Introduction" and in Section 6—"Price Range of Shares; Dividends", Section 7—"Possible Effects of the Offer on the Market for the Shares; NASDAQ Listing; Exchange Act Registration and Margin Regulations" and Section 11—"Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements" of the Offer to Purchase is incorporated herein by reference.

ITEM 7.    SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.

        (a), (d) The information set forth in the section of the Offer to Purchase titled "Summary Term Sheet" and in Section 12—"Source and Amount of Funds" of the Offer to Purchase is incorporated herein by reference.

        (b)   The Offer is not subject to a financing condition.

ITEM 8.    INTEREST IN SECURITIES OF THE SUBJECT COMPANY.

        The information set forth in Section 9—"Certain Information Concerning Parent and Purchaser", Section 11—"Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements" and Schedule A of the Offer to Purchase is incorporated herein by reference.

ITEM 9.    PERSONS/ASSETS RETAINED, EMPLOYED, COMPENSATED OR USED.

        (a)   The information set forth in Section 3—"Procedures for Tendering Shares", Section 10—"Background of the Offer; Contacts with Forty Seven" and Section 16—"Fees and Expenses" of the Offer to Purchase is incorporated herein by reference.

ITEM 10.    FINANCIAL STATEMENTS.

        Not Applicable. In accordance with the instructions to Item 10 of the Schedule TO, the financial statements are not considered material because:

        (a)   the consideration offered consists solely of cash;

        (b)   the Offer is not subject to any financing condition; and

        (c)   the Offer is for all outstanding securities of the subject class.

ITEM 11.    ADDITIONAL INFORMATION.

        (a)   The information set forth in Section 7—"Possible Effects of the Offer on the Market for the Shares; NASDAQ Listing; Exchange Act Registration and Margin Regulations", Section 10—"Background of the Offer; Contacts with Forty Seven", Section 11—"Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements" and Section 15—"Certain Legal Matters; Regulatory Approvals" of the Offer to Purchase is incorporated herein by reference.

        (c)   The information set forth in the Offer to Purchase is incorporated herein by reference.

ITEM 12.    EXHIBITS.

Index No.    
  (a)(1)(A)*   Offer to Purchase, dated March 10, 2020.

 
(a)(1)(B)*
 
Form of Letter of Transmittal.

 
(a)(1)(C)*
 
Form of Notice of Guaranteed Delivery.

 
(a)(1)(D)*
 
Form of Letter to Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.

 
(a)(1)(E)*
 
Form of Letter to Clients for Use by Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.

 
(a)(1)(F)*
 
Form of Summary Advertisement, published March 10, 2020 in The Wall Street Journal.

 
(a)(5)(A)
 
Joint Press Release of Parent and Forty Seven, dated March 2, 2020 (incorporated by reference to Exhibit 99.1 to the Current Report on Form 8-K filed by Parent with the Securities and Exchange Commission on March 2, 2020).

 
(a)(5)(B)
 
Investor Presentation, dated March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 2, 2020).

 
(a)(5)(C)
 
Transcript of Investor Presentation Call on March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 2, 2020).

 
(a)(5)(D)
 
Email sent to Parent employees on March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 2, 2020).

 
(a)(5)(E)
 
Email sent to Parent Operating Group on March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 2, 2020).

 
(a)(5)(F)
 
Frequently Asked Questions, sent to Parent Operating Group on March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 2, 2020).

 
(a)(5)(G)
 
Email sent to Forty Seven's employees on March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 2, 2020).

 
(a)(5)(H)
 
Q&A provided to Forty Seven's employees on March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 2, 2020).

 
(a)(5)(I)
 
Tweet posted by Parent on March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 2, 2020).

 
(a)(5)(J)
 
Transcript of Q&A at Cowen Health Care Conference on March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 3, 2020).

 
(a)(5)(K)
 
Op-ed by Daniel O'Day, posted on Parent's website on March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 3, 2020).

Index No.    
  (a)(5)(L)   Tweet posted by Parent on March 2, 2020 (incorporated by reference to the Tender Offer Statement on Schedule TO-C of Parent filed with the Securities and Exchange Commission on March 3, 2020).

 
(d)(1)
 
Agreement and Plan of Merger, dated March 1, 2020, among Forty Seven, Parent and Purchaser (incorporated by reference to Exhibit 2.1 to the Current Report on Form 8-K filed by Parent with the Securities and Exchange Commission on March 2, 2020).

 
(d)(2)
 
Mutual Confidentiality Agreement, dated January 7, 2020, between Forty Seven and Parent (incorporated by reference to Exhibit (e)(2) to the Schedule 14D-9 filed by Forty Seven with the Securities and Exchange Commission on March 10 2020).

 
(g)
 
Not applicable.

 
(h)
 
Not applicable.
*
Filed herewith.

ITEM 13.    INFORMATION REQUIRED BY SCHEDULE 13E-3.

        Not applicable.


SIGNATURE

        After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: March 10, 2020

    TORO MERGER SUB, INC.

 
 
By:
 
/s/ ANDREW D. DICKINSON
        Name:   Andrew D. Dickinson
        Title:   President and Treasurer

 
 
GILEAD SCIENCES, INC.

 
 
By:
 
/s/ DANIEL P. O'DAY
        Name:   Daniel P. O'Day
        Title:   Chairman and Chief Executive Officer



QuickLinks

SIGNATURE

QuickLinks -- Click here to rapidly navigate through this document


Exhibit (a)(1)(A)

Offer to Purchase
All Outstanding Shares of Common Stock
of

FORTY SEVEN, INC.

At
$95.50 Net Per Share in Cash
by

TORO MERGER SUB, INC.

a wholly owned subsidiary of

GILEAD SCIENCES, INC.

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT ONE MINUTE AFTER
11:59 P.M., EASTERN TIME, ON APRIL 6, 2020,
UNLESS THE OFFER IS EXTENDED OR EARLIER TERMINATED.

        Toro Merger Sub, Inc., a Delaware corporation ("Purchaser"), is offering to purchase (the "Offer") all outstanding shares of common stock, par value $0.0001 per share ("Shares"), of Forty Seven, Inc., a Delaware corporation ("Forty Seven"), at a price per Share of $95.50, net to the holder in cash, without interest (the "Offer Price") upon the terms and subject to the conditions described in this Offer to Purchase (together with any amendments or supplements hereto, this "Offer to Purchase") and in the related Letter of Transmittal (together with any amendments or supplements thereto, the "Letter of Transmittal"). Purchaser is a wholly owned subsidiary of Gilead Sciences, Inc. ("Parent"), a Delaware corporation. The Offer is being made in connection with the Agreement and Plan of Merger, dated as of March 1, 2020 (together with any amendments or supplements thereto, the "Merger Agreement"), among Forty Seven, Parent and Purchaser, pursuant to which, after the completion of the Offer and the satisfaction or waiver of certain conditions, Purchaser will be merged with and into Forty Seven, without a meeting of the Forty Seven stockholders in accordance with Section 251(h) of the General Corporation Law of the State of Delaware (the "DGCL"), and Forty Seven will be the surviving corporation and a wholly owned subsidiary of Parent (such corporation, the "Surviving Corporation" and such merger, the "Merger"). At the effective time of the Merger, all then outstanding Shares, including any Shares subject to vesting or employment based forfeiture conditions (other than (i) Shares held by Forty Seven (or held in the treasury of Forty Seven), (ii) Shares held by Parent, Purchaser or any other direct or indirect wholly owned subsidiary of Parent and (iii) Shares held by stockholders who have properly exercised and perfected their demands for appraisal of such Shares in accordance with the DGCL and have neither withdrawn nor lost such rights prior to the effective time of the Merger), will be converted into the right to receive consideration equal to the Offer Price, without interest, without regard to any applicable vesting or employment based forfeiture conditions, and subject to any applicable withholding of taxes.

        After careful consideration, the Forty Seven board of directors has unanimously: (i) determined that the Merger Agreement and the transactions contemplated thereby, including the Offer and the Merger (the "Transactions"), are fair to, and in the best interest of, Forty Seven and its stockholders, (ii) declared it advisable for Forty Seven to enter into the Merger Agreement, (iii) approved the execution, delivery and performance by Forty Seven of the Merger Agreement and the consummation of the Transactions, (iv) resolved that the Merger shall be effected under Section 251(h) of the DGCL and (v) resolved to recommend that the stockholders of Forty Seven accept the Offer and tender their Shares to Purchaser pursuant to the Offer.

        There is no financing condition to the Offer. The Offer is subject to various conditions. See Section 13—"Conditions of the Offer." A summary of the principal terms of the Offer appears on pages 1 through 7 of this Offer to Purchase. You should read this entire document carefully before deciding whether to tender your Shares.

March 10, 2020


IMPORTANT

        If you desire to tender all or any portion of your Shares to us pursuant to the Offer, you should either (i) if you hold your Shares directly as the registered owner, complete and sign the Letter of Transmittal for the Offer, which is enclosed with this Offer to Purchase, in accordance with the instructions contained in the Letter of Transmittal, mail or deliver the Letter of Transmittal and any other required documents to Computershare Trust Company, N.A. (the "Depositary"), and either deliver the certificates for your Shares to the Depositary along with the Letter of Transmittal or tender your Shares by book-entry transfer by following the procedures described in Section 3—"Procedures for Tendering Shares" of this Offer to Purchase, in each case prior to the expiration of the Offer, or (ii) if you hold your Shares in street name, request that your broker, dealer, commercial bank, trust company or other nominee effect the transaction for you. If you hold Shares registered in the name of a broker, dealer, commercial bank, trust company or other nominee you must contact that institution in order to tender your Shares to us pursuant to the Offer.

        If you desire to tender your Shares to us pursuant to the Offer and the certificates representing your Shares are not immediately available, or you cannot comply in a timely manner with the procedures for tendering your Shares by book-entry transfer, or you cannot deliver all required documents to the Depositary prior to the expiration of the Offer, you may tender your Shares to us pursuant to the Offer by following the procedures for guaranteed delivery described in Section 3—"Procedures for Tendering Shares" of this Offer to Purchase.

* * *

        Questions and requests for assistance may be directed to Innisfree M&A Incorporated (the "Information Agent") at its address and telephone number set forth on the back cover of this Offer to Purchase. Requests for additional copies of this Offer to Purchase, the Letter of Transmittal, the Notice of Guaranteed Delivery and other tender offer materials may be directed to the Information Agent. You may also contact your broker, dealer, commercial bank, trust company or other nominee for assistance.

        This Offer to Purchase and the Letter of Transmittal contain important information, and you should read both carefully and in their entirety before making any decision with respect to the Offer.


TABLE OF CONTENTS

 
    
   Page  

SUMMARY TERM SHEET

     1  

INTRODUCTION

     8  

THE TENDER OFFER

     10  

1.

  

Terms of the Offer

     10  

2.

  

Acceptance for Payment and Payment for Shares

     12  

3.

  

Procedures for Tendering Shares

     13  

4.

  

Withdrawal Rights

     17  

5.

  

Certain U.S. Federal Income Tax Consequences of the Offer and the Merger to U.S. Holders

     17  

6.

  

Price Range of Shares; Dividends

     19  

7.

  

Possible Effects of the Offer on the Market for the Shares; NASDAQ Listing; Exchange Act Registration and Margin Regulations

     19  

8.

  

Certain Information Concerning Forty Seven

     21  

9.

  

Certain Information Concerning Parent and Purchaser

     22  

10.

  

Background of the Offer; Contacts with Forty Seven

     23  

11.

  

Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements

     29  

12.

  

Source and Amount of Funds

     51  

13.

  

Conditions of the Offer

     51  

14.

  

Dividends and Distributions

     53  

15.

  

Certain Legal Matters; Regulatory Approvals

     53  

16.

  

Fees and Expenses

     57  

17.

  

Miscellaneous

     57  

SCHEDULE A

     A-1  

i


 SUMMARY TERM SHEET

        Toro Merger Sub, Inc., a recently formed Delaware corporation ("Purchaser") and a wholly owned subsidiary of Gilead Sciences, Inc., a Delaware corporation ("Parent"), is offering to purchase (the "Offer") all outstanding shares of common stock, par value $0.0001 per share (the "Shares), of Forty Seven, Inc., a Delaware corporation ("Forty Seven"), at a price per Share of $95.50, net to the holder in cash, without interest (the "Offer Price") upon terms and subject to the conditions set forth in this Offer to Purchase (together with any amendments or supplements hereto, this "Offer to Purchase") and in the related Letter of Transmittal (together with any amendments or supplements thereto, the "Letter of Transmittal"). The following are some questions you, as a stockholder of Forty Seven, may have and answers to those questions. This Summary Term Sheet highlights selected information from this Offer to Purchase, and may not contain all of the information that is important to you and is qualified in its entirety by the more detailed descriptions and explanations contained in this Offer to Purchase and the related Letter of Transmittal. To better understand the Offer and for a complete description of the legal terms of the Offer, you should read this Offer to Purchase and the related Letter of Transmittal carefully and in their entirety. Questions or requests for assistance may be directed to Innisfree M&A Incorporated (the "Information Agent") at its address and telephone numbers, as set forth on the back cover of this Offer to Purchase. Unless otherwise indicated in this Offer to Purchase or the context otherwise requires, all references in this Offer to Purchase to "we," "our," or "us" refer to Purchaser or Parent, as the context requires.

WHO IS OFFERING TO BUY MY SECURITIES?

WHAT ARE THE CLASSES AND AMOUNTS OF SECURITIES SOUGHT IN THE OFFER?

HOW MUCH ARE YOU OFFERING TO PAY AND WHAT IS THE FORM OF PAYMENT? WILL I HAVE TO PAY ANY FEES OR COMMISSIONS?

WHY IS PURCHASER MAKING THE OFFER?

WHAT ARE THE MOST SIGNIFICANT CONDITIONS OF THE OFFER?

2

IS THERE AN AGREEMENT GOVERNING THE OFFER?

DO YOU HAVE FINANCIAL RESOURCES TO MAKE PAYMENTS IN THE OFFER?

SHOULD PURCHASER'S FINANCIAL CONDITION BE RELEVANT TO MY DECISION TO TENDER IN THE OFFER?

HOW LONG DO I HAVE TO DECIDE WHETHER TO TENDER IN THE OFFER?

CAN THE OFFER BE EXTENDED, AND UNDER WHAT CIRCUMSTANCES?

3

HOW WILL I BE NOTIFIED IF THE OFFER IS EXTENDED?

HOW DO I TENDER MY SHARES?

UNTIL WHAT TIME CAN I WITHDRAW PREVIOUSLY TENDERED SHARES?

HOW DO I WITHDRAW PREVIOUSLY TENDERED SHARES?

4

WHAT DOES FORTY SEVEN'S BOARD OF DIRECTORS THINK OF THE OFFER?

WILL THE TENDER OFFER BE FOLLOWED BY A MERGER IF ALL THE SHARES ARE NOT TENDERED?

IF THE OFFER IS COMPLETED, WILL FORTY SEVEN CONTINUE AS A PUBLIC COMPANY?

IF I DECIDE NOT TO TENDER, HOW WILL THE OFFER AFFECT MY SHARES?

5

WHAT IS THE MARKET VALUE OF MY SHARES AS OF A RECENT DATE?

IF I ACCEPT THE OFFER, WHEN AND HOW WILL I GET PAID?

IF I AM AN EMPLOYEE OF FORTY SEVEN, HOW WILL MY OUTSTANDING EQUITY AWARDS BE TREATED IN THE OFFER AND THE MERGER?

WHAT ARE THE PRINCIPAL U.S. FEDERAL INCOME TAX CONSEQUENCES OF TENDERING MY SHARES IN THE OFFER OR HAVING MY SHARES EXCHANGED FOR CASH PURSUANT TO THE MERGER?

6

WILL I HAVE THE RIGHT TO HAVE MY SHARES APPRAISED?

WITH WHOM MAY I TALK IF I HAVE QUESTIONS ABOUT THE OFFER?

Except as otherwise set forth in this Offer to Purchase, references to "dollars" and "$" shall be to United States dollars.

7

To All Holders of Shares of
FORTY SEVEN, INC.

INTRODUCTION

        Toro Merger Sub, Inc., a Delaware corporation ("Purchaser"), is offering to purchase (the "Offer") all outstanding shares of common stock, par value $0.0001 per share (the "Shares"), of Forty Seven, Inc., a Delaware corporation ("Forty Seven"), at a price per Share of $95.50, net to the holder in cash, without interest (the "Offer Price") upon the terms and subject to the conditions described in this Offer to Purchase (together with any amendments or supplements hereto, this "Offer to Purchase") and in the related Letter of Transmittal (together with any amendments or supplements thereto, the "Letter of Transmittal"). Purchaser is a wholly owned subsidiary of Gilead Sciences, Inc. ("Parent").

        The Offer is being made in connection with the Agreement and Plan of Merger, dated as of March 1, 2020 (together with any amendments or supplements thereto, the "Merger Agreement"), among Forty Seven, Parent and Purchaser, pursuant to which, after the completion of the Offer and the satisfaction or waiver of certain conditions, Purchaser will be merged with and into Forty Seven, and Forty Seven will be the surviving corporation and a wholly owned subsidiary of Parent (such corporation, the "Surviving Corporation" and such merger, the "Merger").

        If your Shares are registered in your name and you tender directly to Computershare Trust Company, N.A., the depositary for the Offer (the "Depositary") you will not be obligated to pay brokerage fees or commissions or, except as otherwise provided in Instruction 6 of the Letter of Transmittal, transfer taxes on the purchase of Shares by Purchaser pursuant to the Offer. If you hold your Shares through a broker, dealer, commercial bank, trust company or other nominee you should check with such institution as to whether they charge any service fees or commissions.

        In addition, if you do not complete and sign the Internal Revenue Service ("IRS") Form W-9 that is provided with the Letter of Transmittal, or an IRS Form W-8BEN or other IRS Form W-8, as applicable, or otherwise establish an exemption, you may be subject to U.S. federal backup withholding (at a rate currently equal to 24%) on the gross proceeds payable to you pursuant to the Offer or the Merger. Backup withholding is not an additional tax and any amounts withheld under the backup withholding rules may be refunded or credited against your U.S. federal income tax liability, provided the required information is timely furnished in the appropriate manner to the IRS. All stockholders should review the discussion in Section 3—"Procedures for Tendering Shares" and Section 5—"Certain U.S. Federal Income Tax Consequences of the Offer and the Merger to U.S. Holders."

        We will pay all charges and expenses of the Depositary and Innisfree M&A Incorporated, the information agent for the Offer (the "Information Agent").

        The Offer is not subject to any financing condition. The Offer is subject to the conditions, among others, that:

8

        Purchaser and Parent have the right to waive certain of the conditions to the Offer in their sole discretion; provided that Parent may not waive the Minimum Tender Condition, the Termination Condition, the HSR Condition or the Governmental Impediment Condition without the consent of Forty Seven. See Section 13—"Conditions of the Offer."

        The Offer will expire at one minute after 11:59 p.m., Eastern Time, on April 6, 2020, unless the Offer is extended. See Section 1—"Terms of the Offer", Section 13—"Conditions of the Offer" and Section 15—"Certain Legal Matters; Regulatory Approvals."

        After careful consideration, the Forty Seven board of directors (the "Forty Seven Board") has unanimously: (i) determined that the Merger Agreement and the transactions contemplated thereby, including the Offer and the Merger (the "Transactions"), are fair to, and in the best interest of, Forty Seven and its stockholders, (ii) declared it advisable for Forty Seven to enter into the Merger Agreement, (iii) approved the execution, delivery and performance by Forty Seven of the Merger Agreement and the consummation of the Transactions, (iv) resolved that the Merger shall be effected under Section 251(h) of the General Corporation Law of the State of Delaware (the "DGCL") and (v) resolved to recommend that the stockholders of Forty Seven accept the Offer and tender their Shares to Purchaser pursuant to the Offer.

        For factors considered by the Forty Seven Board, see Forty Seven's Solicitation/Recommendation Statement on Schedule 14D-9 (the "Schedule 14D-9") filed with the Securities and Exchange Commission (the "SEC") in connection with the Offer, a copy of which (without certain exhibits) is being furnished to stockholders concurrently herewith.

        The Offer is being made in connection with the Merger Agreement, pursuant to which, after the completion of the Offer and the satisfaction or waiver of certain conditions, the Merger will be effected. The Merger shall become effective when a certificate of merger is filed with the Secretary of State of the State of Delaware (or at such subsequent date and time as may be agreed by Parent, Forty Seven and Purchaser and specified in the certificate of merger) (the "Effective Time").

        At the Effective Time, each Share issued and outstanding immediately prior to the Effective Time, including any Shares subject to vesting or employment based forfeiture conditions (other than (i) any Shares held by Forty Seven (or held in the treasury of Forty Seven), (ii) each Share owned by Parent, Purchaser or any other direct or indirect wholly owned subsidiary of Parent immediately prior to the Effective Time which will be canceled without any conversion thereof and no consideration will be delivered in exchange therefor and (iii) any Shares owned by Forty Seven's stockholders who have

9

properly exercised and perfected their demands for appraisal of such Shares in accordance with the DGCL and have neither withdrawn nor lost such rights prior to the Effective Time) will be canceled and will be converted automatically into the right to receive consideration equal to the Offer Price payable, without any interest, without regard to any applicable vesting or employment based forfeiture conditions, and subject to any withholding taxes, to the holder of such Share, upon surrender of the certificate that formerly evidenced such Share or, with respect to uncertificated Shares, upon the receipt by the Depositary of an Agent's Message (as defined below) relating to such Shares.

        The Merger Agreement is more fully described in Section 11—"Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements," which also contains a discussion of the treatment of Forty Seven stock options in the Merger. Section 5—"Certain U.S. Federal Income Tax Consequences of the Offer and the Merger to U.S. Holders" below describes certain U.S. federal income tax consequences generally applicable to U.S. Holders (as defined below) whose Shares are tendered and accepted for purchase pursuant to the Offer or whose Shares are converted into the right to receive cash in the Merger.

        Because the Merger will be consummated in accordance with Section 251(h) of the DGCL, approval of the Merger will not require a vote of Forty Seven's stockholders. Section 251(h) of the DGCL provides that stockholder approval of a merger is not required if certain requirements are met, including that (i) the acquiring company consummates a tender offer for any and all of the outstanding stock of the company to be acquired that, absent Section 251(h) of the DGCL, would be entitled to vote on the merger, (ii) following the consummation of such tender offer, the acquiring company owns at least such percentage of the stock of the company to be acquired that, absent Section 251(h) of the DGCL, would be required to adopt the merger agreement, and (iii) at the time that the board of directors of the company to be acquired approves the merger agreement, no other party to the merger agreement is an "interested stockholder" under the DGCL. If the Minimum Tender Condition is satisfied and we accept Shares for payment pursuant to the Offer, we will hold a sufficient number of Shares to ensure that Forty Seven will not be required to submit the adoption of the Merger Agreement to a vote of its stockholders. As a result of the Merger, Forty Seven will cease to be a publicly traded company and will become a wholly owned subsidiary of Parent. See Section 11—"Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements."

        This Offer to Purchase and the related Letter of Transmittal contain important information and both documents should be read carefully and in their entirety before any decision is made with respect to the Offer.


 THE TENDER OFFER

1.     Terms of the Offer.

        Upon the terms and subject to the prior satisfaction or waiver of the conditions of the Offer (including, if the Offer is extended or amended, the terms and conditions of any extension or amendment), we will accept for payment, purchase and pay for all Shares validly tendered prior to the expiration of the Offer, and not properly withdrawn in accordance with the procedures set forth in Section 4—"Withdrawal Rights." The offer will expire at one minute after 11:59 p.m. Eastern Time on Monday, April 6, 2020 (the "Expiration Date"), unless we have extended the Offer in accordance with the terms of the Merger Agreement, in which event the term "Expiration Date" will mean the date to which the initial expiration date of the Offer is so extended.

        The Offer is conditioned upon the satisfaction of the Minimum Tender Condition and the other conditions described in Section 13—"Conditions of the Offer." We may terminate the Offer without purchasing any Shares if certain events described in Section 11—"Purpose of the Offer and Plans for

10

Forty Seven; Summary of the Merger Agreement and Certain Other Agreements—Summary of the Merger Agreement—Termination" occur.

        Purchaser expressly reserves the right to (i) waive (to the extent permitted under applicable legal requirements) any Offer Condition, (ii) increase the amount of cash constituting the Offer Price and (iii) make any other changes in the terms and conditions of the Offer that are not inconsistent with the terms of the Merger Agreement, except that Forty Seven's prior written approval is required for Parent or Purchaser to:

        Upon the terms and subject to the satisfaction or waiver of the conditions of the Offer and the Merger Agreement, we will (i) immediately after the Expiration Date irrevocably accept for payment all Shares tendered (and not validly withdrawn) pursuant to the Offer and (ii) as promptly as practicable thereafter (and in any event within three (3) business days) pay for all such shares. The time at which Purchaser accepts for payment Shares tendered in the Offer is referred to as the "Offer Acceptance Time."

        If, on or before the Expiration Date, we increase the consideration being paid for Shares accepted for payment in the Offer, such increased consideration will be paid to all stockholders whose Shares are purchased in the Offer, whether or not such Shares were tendered before the announcement of the increase in consideration. We also expressly reserve the right to modify the terms of the Offer, subject to compliance with the Exchange Act, the Merger Agreement and the restrictions identified in paragraphs (1) through (8) above.

        The Merger Agreement provides that (i) if at any then-scheduled Expiration Date any condition to the Offer is not satisfied (unless such condition is waivable by Purchaser or Parent and has been waived), Purchaser has agreed to extend the offer for additional periods of up to ten (10) business days per extension in order to permit such condition to be satisfied, and (ii) Purchaser has agreed to extend the Offer for any period required by any applicable legal requirement, or any interpretation or position of the SEC or the Nasdaq Global Select Market ("NASDAQ") applicable to the Offer, in each case until the earlier of (x) termination of the Merger Agreement in accordance with its terms or (y) June 1, 2020 (or September 1, 2020, in the event that certain conditions to the Offer have not been satisfied as of such earlier date as provided in the Merger Agreement). See Section 11—"Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements."

11

        Except as set forth above, there can be no assurance that we will be required under the Merger Agreement to extend the Offer. During any extension of the initial offering period pursuant to the paragraphs above, all Shares previously tendered and not withdrawn will remain subject to the Offer and subject to withdrawal rights. See Section 4—"Withdrawal Rights."

        Without Forty Seven's consent, there will not be a subsequent offering period for the Offer.

        If, subject to the terms of the Merger Agreement, we make a material change in the terms of the Offer or the information concerning the Offer, or if we waive a material condition of the Offer, we will disseminate additional tender offer materials and extend the Offer if and to the extent required by Rules 14d-3(b)(1), 14d-4(d), 14d-6(c) and l4e-1 under the Exchange Act or otherwise. The minimum period during which a tender offer must remain open following material changes in the terms of the tender offer or the information concerning the tender offer, other than a change in the consideration offered or a change in the percentage of securities sought, will depend upon the facts and circumstances, including the relative materiality of the terms or information changes. With respect to a change in the consideration offered or a change in the percentage of securities sought, a tender offer generally must remain open for a minimum of ten (10) business days following such change to allow for adequate disclosure to stockholders.

        We expressly reserve the right, in our sole discretion, subject to the terms and upon the conditions of the Merger Agreement and the applicable rules and regulations of the SEC, to not accept for payment any Shares if, at the expiration of the Offer, any of the conditions to the Offer set forth in Section 13—"Conditions of the Offer" have not been satisfied. Under certain circumstances, Parent and Purchaser may terminate the Merger Agreement and the Offer.

        Any extension, waiver or amendment of the Offer or termination of the Offer will be followed, as promptly as practicable, by public announcement thereof, such announcement in the case of an extension to be issued not later than 9:00 a.m., Eastern Time, on the next business day after the Expiration Date in accordance with the public announcement requirements of Rules 14d-3(b)(1), 14d-4(d), 14d-6(c) and l4e-1(d) under the Exchange Act. Without limiting our obligation under such rule or the manner in which we may choose to make any public announcement, we currently intend to make announcements by issuing a press release to the PR Newswire (or such other national media outlet or outlets we deem prudent) and making any appropriate filing with the SEC.

        Promptly following the purchase of Shares in the Offer, we expect to complete the Merger without a vote of the stockholders of Forty Seven pursuant to Section 251(h) of the DGCL.

        Forty Seven has agreed to provide us with its list of stockholders and security position listings for the purpose of disseminating the Offer to holders of Shares. This Offer to Purchase and the related Letter of Transmittal will be mailed to record holders of Shares whose names appear on Forty Seven's stockholder list and will be furnished to brokers, dealers, commercial banks, trust companies and similar persons whose names, or the names of whose nominees, appear on the stockholder list or, if applicable, who are listed as participants in a clearing agency's security position listing, for subsequent transmittal to beneficial owners of Shares.

2.     Acceptance for Payment and Payment for Shares.

        Subject to the satisfaction or waiver of all the conditions to the Offer set forth in Section 13—"Conditions of the Offer," we will immediately after the Expiration Date irrevocably accept for payment all Shares tendered (and not validly withdrawn) pursuant to the Offer and, promptly after the Offer Acceptance Time (and in any event within three (3) business days), pay for such Shares.

        In all cases, payment for Shares tendered and accepted for payment pursuant to the Offer will be made only after timely receipt by the Depositary of (i) certificates representing such Shares or confirmation of the book-entry transfer of such Shares into the Depositary's account at The Depository

12

Trust Company ("DTC") pursuant to the procedures set forth in Section 3—"Procedures for Tendering Shares," (ii) a Letter of Transmittal, properly completed and duly executed, with any required signature guarantees (or, in the case of a book-entry transfer, an Agent's Message (as defined below) in lieu of the Letter of Transmittal), and (iii) any other documents required by the Letter of Transmittal or any other customary documents required by Depositary. See Section 3—"Procedures for Tendering Shares."

        For purposes of the Offer, if and when Purchaser gives oral or written notice to the Depositary of its acceptance for payment of such Shares pursuant to the Offer, then Purchaser has accepted for payment and thereby purchased Shares validly tendered and not validly withdrawn pursuant to the Offer. Upon the terms and subject to the conditions of the Offer, payment for Shares accepted for payment pursuant to the Offer will be made by deposit of the purchase price therefor with the Depositary, which will act as agent for the tendering stockholders for purposes of receiving payments from us and transmitting such payments to the tendering stockholders. Under no circumstances will interest be paid on the Offer Price for Shares, regardless of any extension of the Offer or any delay in payment for Shares.

        If any tendered Shares are not accepted for payment pursuant to the terms and conditions of the Offer for any reason, or if certificates are submitted for more Shares than are tendered, certificates for such unpurchased Shares will be returned (or new certificates for the Shares not tendered will be sent), without expense to the tendering stockholder (or, in the case of Shares tendered by book-entry transfer into the Depositary's account at DTC pursuant to the procedures set forth in Section 3—"Procedures for Tendering Shares," such Shares will be credited to an account maintained with DTC) promptly following expiration or termination of the Offer.

3.     Procedures for Tendering Shares.

        Valid Tender of Shares.    Except as set forth below, to validly tender Shares pursuant to the Offer, (i) a properly completed and duly executed Letter of Transmittal in accordance with the instructions of the Letter of Transmittal, with any required signature guarantees, or an Agent's Message (as defined below) in connection with a book-entry delivery of Shares, and any other documents required by the Letter of Transmittal and any other customary documents required by the Depositary, must be received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase prior to the expiration of the Offer and either (a) certificates representing Shares tendered must be delivered to the Depositary or (b) such Shares must be properly delivered pursuant to the procedures for book-entry transfer described below and a confirmation of such delivery received by the Depositary (which confirmation must include an Agent's Message (as defined below) if the tendering stockholder has not delivered a Letter of Transmittal), in each case, prior to the Expiration Date or (ii) the tendering stockholder must comply with the guaranteed delivery procedures set forth below. The term "Agent's Message" means a message, transmitted by DTC to, and received by, the Depositary and forming a part of a Book-Entry Confirmation (as defined below), which states that DTC has received an express acknowledgment from the participant in DTC tendering the Shares which are the subject of such Book-Entry Confirmation (as defined below) that such participant has received and agrees to be bound by the terms of the Letter of Transmittal and that Purchaser may enforce such agreement against the participant.

        Book-Entry Transfer.    The Depositary will take steps to establish and maintain an account with respect to the Shares at DTC for purposes of the Offer. Any financial institution that is a participant in DTC's systems may make a book-entry transfer of Shares by causing DTC to transfer such Shares into the Depositary's account in accordance with DTC's procedures for such transfer. However, although delivery of Shares may be effected through book-entry transfer, either the Letter of Transmittal, properly completed and duly executed, together with any required signature guarantees, or an Agent's Message in lieu of the Letter of Transmittal, and any other required documents, must, in any case, be transmitted to and received by the Depositary at one of its addresses set forth on the back cover of this

13

Offer to Purchase prior to the Expiration Date or the tendering stockholder must comply with the guaranteed delivery procedures described below. The confirmation of a book-entry transfer of Shares into the Depositary's account at DTC as described above is referred to herein as a "Book-Entry Confirmation."

        Delivery of documents to DTC in accordance with DTC's procedures does not constitute delivery to the Depositary.

        Signature Guarantees and Stock Powers.    Except as otherwise provided below, all signatures on a Letter of Transmittal must be guaranteed by a financial institution (including most commercial banks, savings and loan associations and brokerage houses) that is a member in good standing of a recognized Medallion Program approved by the Securities Transfer Association, Inc., including the Security Transfer Agents Medallion Program, the New York Stock Exchange Medallion Signature Program and the Stock Exchanges Medallion Program (each, an "Eligible Institution"). Signatures on a Letter of Transmittal need not be guaranteed (i) if the Letter of Transmittal is signed by the registered owner(s) (which term, for purposes of this section, includes any participant in any of DTC's systems whose name appears on a security position listing as the owner of the Shares) of Shares tendered therewith and such registered owner has not completed the box entitled "Special Payment Instructions" or the box entitled "Special Delivery Instructions" on the Letter of Transmittal or (ii) if such Shares are tendered for the account of an Eligible Institution. See Instructions 1 and 5 of the Letter of Transmittal. If the certificates for Shares are registered in the name of a person other than the signer of the Letter of Transmittal, or if payment is to be made or certificates for Shares not tendered or not accepted for payment are to be returned to a person other than the registered owner of the certificates surrendered, then the tendered certificates must be registered or accompanied by appropriate stock powers, in either case, signed exactly as the name or names of the registered owner(s) or holder(s) appear on the certificates, with the signatures on the certificates or stock powers guaranteed as described above. See Instructions 1 and 5 of the Letter of Transmittal.

        If certificates representing Shares are forwarded separately to the Depositary, a properly completed and duly executed Letter of Transmittal must accompany each delivery of certificates.

        Guaranteed Delivery.    A stockholder who desires to tender Shares pursuant to the Offer and whose certificates for Shares are not immediately available and cannot be delivered to the Depositary prior to the expiration of the Offer, or who cannot complete the procedure for book-entry transfer prior to the expiration of the Offer, or who cannot deliver all required documents to the Depositary prior to the expiration of the Offer, may tender such Shares by satisfying all of the requirements set forth below:

        The Notice of Guaranteed Delivery may be delivered by overnight courier to the Depositary or mailed to the Depositary and must include a guarantee by an Eligible Institution in the form set forth in such Notice of Guaranteed Delivery. Shares tendered by a Notice of Guaranteed Delivery will not

14

be deemed validly tendered for purposes of satisfying the Minimum Tender Condition unless and until Shares underlying such Notice of Guaranteed Delivery are delivered to the Depositary prior to the expiration of the Offer.

        THE METHOD OF DELIVERY OF SHARES, THE LETTER OF TRANSMITTAL AND ALL OTHER REQUIRED DOCUMENTS, INCLUDING DELIVERY THROUGH DTC, IS AT THE ELECTION AND RISK OF THE TENDERING STOCKHOLDER. DELIVERY OF ALL SUCH DOCUMENTS WILL BE DEEMED MADE ONLY WHEN ACTUALLY RECEIVED BY THE DEPOSITARY (INCLUDING, IN THE CASE OF A BOOK-ENTRY TRANSFER, BY BOOK-ENTRY CONFIRMATION). IF SUCH DELIVERY IS BY MAIL, IT IS RECOMMENDED THAT ALL SUCH DOCUMENTS BE SENT BY PROPERLY INSURED REGISTERED MAIL WITH RETURN RECEIPT REQUESTED. IN ALL CASES, SUFFICIENT TIME SHOULD BE ALLOWED TO ENSURE TIMELY DELIVERY.

        Other Requirements.    Notwithstanding any provision of the Merger Agreement, Purchaser will pay for Shares tendered (and not validly withdrawn) pursuant to the Offer only after timely receipt by the Depositary of (i) certificates for (or a timely Book-Entry Confirmation with respect to) such Shares, (ii) a Letter of Transmittal, properly completed and duly executed, with any required signature guarantees (or, in the case of a book-entry transfer, an Agent's Message in lieu of the Letter of Transmittal), and (iii) any other documents required by the Letter of Transmittal or any other customary documents required by the Depositary. Accordingly, tendering stockholders may be paid at different times depending upon when certificates for Shares or Book-Entry Confirmations with respect to Shares are actually received by the Depositary. Under no circumstances will Purchaser pay interest on the purchase price of Shares, regardless of any extension of the Offer or any delay in making such payment. If your Shares are held in street name (i.e., through a broker, dealer, commercial bank, trust company or other nominee), your Shares can be tendered by your nominee by book-entry transfer through the Depositary. If you are unable to deliver any required document or instrument to the Depositary by the expiration of the Offer, you may gain some extra time by having a broker, a bank or other fiduciary that is an eligible guarantor institution guarantee that the missing items will be received by the Depositary by using the enclosed Notice of Guaranteed Delivery. For the tender to be valid, however, the Depositary must receive the missing items together with the Shares within two (2) NASDAQ trading days after the date of execution of the Notice of Guaranteed Delivery.

        Binding Agreement.    Our acceptance for payment of Shares tendered pursuant to one of the procedures described above will constitute a binding agreement between the tendering stockholder and us upon the terms and subject to the conditions of the Offer.

        Appointment as Proxy.    By executing and delivering a Letter of Transmittal as set forth above (or, in the case of a book-entry transfer, by delivery of an Agent's Message in lieu of a Letter of Transmittal), the tendering stockholder irrevocably appoints Purchaser's designees as such stockholder's proxies, each with full power of substitution, to the full extent of such stockholder's rights with respect to the Shares tendered by such stockholder and accepted for payment by us and with respect to any and all other Shares or other securities issued or issuable in respect of such Shares on or after the date of the Merger Agreement. All such proxies and powers of attorney will be considered coupled with an interest in the tendered Shares. Such appointment is effective when, and only to the extent that, we accept for payment Shares tendered by such stockholder as provided herein. Upon the effectiveness of such appointment, all prior powers of attorney, proxies and consents given by such stockholder will be revoked, and no subsequent powers of attorney, proxies and consents may be given (and, if given, will not be deemed effective). Our designees will, with respect to the Shares or other securities and rights for which the appointment is effective, be empowered to exercise all voting and other rights of such stockholder as they, in their sole discretion, may deem proper at any annual, special, adjourned or postponed meeting of the stockholders of Forty Seven, by written consent in lieu of any such meeting

15

or otherwise. We reserve the right to require that, in order for Shares to be deemed validly tendered, immediately upon our payment for such Shares we must be able to exercise full voting, consent and other rights to the extent permitted under applicable law with respect to such Shares and other securities, including voting at any meeting of stockholders or executing a written consent concerning any matter.

        Determination of Validity.    All questions as to the validity, form, eligibility (including time of receipt) and acceptance of any tender of Shares will be determined by us in our sole and absolute discretion, which determination will be final and binding, subject to the rights of the tendering holders of Shares to challenge our determination in a court of competent jurisdiction. Purchaser reserves the absolute right to reject any and all tenders determined by us not to be in proper form or the acceptance for payment of or payment for which may, in our opinion, be unlawful. Purchaser also reserves the absolute right to waive any defect or irregularity in the tender of any Shares of any particular stockholder whether or not similar defects or irregularities are waived in the case of any other stockholder. No tender of Shares will be deemed to have been validly made until all defects and irregularities relating thereto have been cured or waived. None of Parent, Purchaser or any of their respective affiliates or assigns, the Depositary, the Information Agent, or any other person will be under any duty to give notification of any defects or irregularities in tenders or incur any liability for failure to give any such notification. Purchaser's interpretation of the terms and conditions of the Offer (including the Letter of Transmittal and the instructions thereto and any other documents related to the Offer) will be final and binding, subject to the rights of the tendering holders of Shares to challenge our determination in a court of competent jurisdiction.

        Backup Withholding.    In order to avoid "backup withholding" of U.S. federal income tax on payments of cash pursuant to the Offer or the Merger, a stockholder that is a "U.S. person" (as defined in the instructions to the IRS Form W-9 provided with the Letter of Transmittal) who surrenders Shares for cash pursuant to the Offer or the Merger must, unless an exemption applies, provide the Depositary with such stockholder's correct taxpayer identification number ("TIN") on an IRS Form W-9, certify under penalties of perjury that such TIN is correct and provide certain other certifications. If a stockholder does not provide such stockholder's correct TIN or fails to provide the required certifications, the IRS may impose penalties on such stockholder, and the gross proceeds payable to such stockholder pursuant to the Offer or the Merger may be subject to backup withholding at a rate currently equal to 24%. All stockholders that are U.S. persons surrendering Shares pursuant to the Offer or the Merger should complete and sign the IRS Form W-9 included as part of the Letter of Transmittal to provide the information and certifications required to avoid backup withholding (unless an applicable exemption exists and is established in a manner satisfactory to the Depositary).

        Certain stockholders (including, among others, all corporations and certain foreign individuals and entities) are not subject to backup withholding. Exempt stockholders that are "U.S. persons" should complete and sign an IRS Form W-9 indicating their exempt status in order to avoid backup withholding. Stockholders that are not "U.S. persons" should complete and sign an IRS Form W-8BEN, IRS Form W-8BEN-E, or other appropriate IRS Form W-8 (instead of an IRS Form W-9) in order to avoid backup withholding. An appropriate IRS Form W-8 may be obtained from the Depositary or at the IRS website (www.irs.gov). See Instruction 8 to the Letter of Transmittal.

        Backup withholding is not an additional tax and any amounts withheld under the backup withholding rules may be refunded or credited against your U.S. federal income tax liability, provided the required information is timely furnished in the appropriate manner to the IRS.

        Information reporting to the IRS may also apply to the receipt of cash pursuant to the Offer or the Merger.

16

4.     Withdrawal Rights.

        Except as otherwise provided in this Section 4, tenders of Shares pursuant to the Offer are irrevocable. However, a stockholder has withdrawal rights that are exercisable until the expiration of the Offer (i.e., at any time prior to one minute after 11:59 p.m., Eastern Time on April 6, 2020), or in the event the Offer is extended, on such date and time to which the Offer is extended. In addition, Shares may be withdrawn at any time after May 9, 2020, which is the 60th day after the date of the commencement of the Offer, unless prior to that date Purchaser has accepted for payment the Shares validly tendered in the Offer.

        For a withdrawal of Shares to be effective, a written or facsimile transmission notice of withdrawal must be timely received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase. Any notice of withdrawal must specify the name of the person having tendered the Shares to be withdrawn, the number of Shares to be withdrawn and the name of the record holder of the Shares to be withdrawn, if different from that of the person who tendered such Shares. The signature(s) on the notice of withdrawal must be guaranteed by an Eligible Institution, unless such Shares have been tendered for the account of any Eligible Institution. If Shares have been tendered pursuant to the procedures for book-entry transfer as set forth in Section 3—"Procedures for Tendering Shares," any notice of withdrawal must specify the name and number of the account at DTC to be credited with the withdrawn Shares. If certificates representing the Shares have been delivered or otherwise identified to the Depositary, the name of the registered owner and the serial numbers shown on such certificates must also be furnished to the Depositary prior to the physical release of such certificates.

        All questions as to the form and validity (including time of receipt) of any notice of withdrawal will be determined by us, in our sole discretion, which determination will be final and binding, subject to the rights of the tendering holders of Shares to challenge our determination in a court of competent jurisdiction. No withdrawal of Shares will be deemed to have been properly made until all defects and irregularities have been cured or waived. None of Parent, Purchaser or any of their respective affiliates or assigns, the Depositary, the Information Agent, or any other person will be under any duty to give notification of any defects or irregularities in any notice of withdrawal or incur any liability for failure to give such notification. Withdrawals of tenders of Shares may not be rescinded, and any Shares properly withdrawn will be deemed not to have been validly tendered for purposes of the Offer. However, withdrawn Shares may be retendered by following one of the procedures for tendering Shares described in Section 3—"Procedures for Tendering Shares" at any time prior to the expiration of the Offer.

        If Purchaser extends the Offer, delays its acceptance for payment of Shares, or is unable to accept for payment Shares pursuant to the Offer, for any reason, then, without prejudice to Purchaser's rights under the Offer, the Depositary may nevertheless, on Purchaser's behalf, retain tendered Shares, and such Shares may not be withdrawn except to the extent that tendering stockholders exercise withdrawal rights as described in this Section 4.

5.     Certain U.S. Federal Income Tax Consequences of the Offer and the Merger to U.S. Holders.

        The following summary describes certain U.S. federal income tax consequences generally applicable to U.S. Holders (as defined below) whose Shares are tendered and accepted for purchase pursuant to the Offer or whose Shares are converted into the right to receive cash in the Merger. This summary is based on the Internal Revenue Code of 1986, as amended (the "Code"), Treasury Regulations promulgated under the Code, published rulings, administrative pronouncements, and judicial decisions, all as in effect on the date hereof and all of which are subject to change or differing interpretations, possibly with retroactive effect. This summary addresses only stockholders who hold their Shares as capital assets within the meaning of the Code (generally, property held for investment)

17

and does not address all of the tax consequences that may be relevant to stockholders in light of their particular circumstances or to certain types of stockholders subject to special treatment under the Code, including pass-through entities (including partnerships and S corporations for U.S. federal income tax purposes) and investors in such entities, certain financial institutions, brokers, dealers or traders in securities, insurance companies, expatriates, mutual funds, real estate investment trusts, regulated investment companies, cooperatives, tax-exempt organizations (including private foundations), persons who are subject to the alternative minimum tax, persons who hold their Shares as part of a straddle, hedge, conversion, constructive sale, synthetic security, integrated investment, or other risk-reduction transaction for U.S. federal income tax purposes, stockholders that have a functional currency other than the U.S. dollar, and persons who acquired their Shares upon the exercise of stock options or otherwise as compensation. This summary does not address the U.S. federal income tax consequences to persons other than U.S. Holders (as defined below). This summary does not address any U.S. federal estate, gift, or other non-income tax consequences, the effects of the Medicare contribution tax on net investment income, or any state, local, or foreign tax consequences.

        For purposes of this discussion, a "U.S. Holder" is a beneficial holder of Shares that, for U.S. federal income tax purposes, is (i) a citizen or individual resident of the United States, (ii) a corporation, or other entity treated as a corporation for U.S. federal income tax purposes, that is created or organized in or under the laws of the United States or any State or the District of Columbia, (iii) an estate, the income of which is subject to U.S. federal income taxation regardless of its source, or (iv) a trust if it (A) is subject to the primary supervision of a court within the United States and one or more U.S. persons have the authority to control all substantial decisions of the trust or (B) has a valid election in effect under applicable Treasury Regulations to be treated as a U.S. person.

        If a partnership (including any entity or arrangement treated as a partnership for U.S. federal income tax purposes) exchanges Shares for cash pursuant to the Offer or the Merger, the tax treatment of a partner in the partnership will generally depend upon the status of the partner and the activities of the partnership. A partner in a partnership holding Shares should consult its tax advisor regarding the tax consequences of exchanging Shares for cash pursuant to the Offer or the Merger.

        Stockholders are urged to consult their tax advisors to determine the tax consequences to them of exchanging Shares for cash pursuant to the Offer or the Merger in light of their particular circumstances.

        The exchange of Shares for cash pursuant to the Offer or the Merger will be a taxable transaction to U.S. Holders for U.S. federal income tax purposes. In general, a U.S. Holder who exchanges Shares for cash pursuant to the Offer or the Merger will recognize capital gain or loss in an amount equal to the difference, if any, between the amount of cash received and the U.S. Holder's adjusted tax basis in the Shares exchanged. Such gain or loss will generally be long-term capital gain or loss if, as of the date of the exchange, a U.S. Holder's holding period in the Shares exchanged is more than one year. Long-term capital gain recognized by certain non-corporate holders, including individuals, is currently subject to tax at a reduced rate. The deductibility of capital losses is subject to limitations under the Code.

        If a U.S. Holder acquired different blocks of Shares at different times or at different prices, such U.S. Holder generally must determine its adjusted tax basis and holding period separately with respect to each such block of Shares.

        A U.S. Holder who exchanges Shares for cash pursuant to the Offer or the Merger is subject to information reporting and may be subject to backup withholding unless certain information is provided to the Depositary or an exemption applies. See Section 3—"Procedures for Tendering Shares."

18

6.     Price Range of Shares; Dividends.

        According to Forty Seven's Annual Report on Form 10-K for the fiscal year ended December 31, 2018, the Shares are traded on the NASDAQ under the symbol "FTSV." Forty Seven has advised Parent that, as of the close of business on February 29, 2020, 48,145,009 Shares were outstanding. The following table sets forth, for the fiscal quarters indicated, the high and low sales prices per Share on NASDAQ with respect to the fiscal years ended December 31, 2018 and December 31, 2019 and, with respect to the fiscal year ended December 31, 2020, through March 9, 2020, using Share data reported by NASDAQ.

Fiscal Year Ended December 31, 2018
  High   Low  

First Quarter

   $ —   $ —  

Second Quarter

     —     —  

Third Quarter

     16.86     12.50  

Fourth Quarter

     23.83     12.02  

 

Fiscal Year Ended December 31, 2019
  High   Low  

First Quarter

   $ 18.82   $ 13.00  

Second Quarter

     19.67     9.90  

Third Quarter

     10.86     6.04  

Fourth Quarter

     45.39     5.53  

 

Current Fiscal Year
  High   Low  

First Quarter (through March 9, 2020)

   $ 94.73   $ 32.29  

        On February 28, 2020, the trading day before the public announcement of the execution of the Merger Agreement, the reported closing sales price of the Shares on NASDAQ was $58.00. On March 9, 2020, the last full trading day prior to the commencement of the Offer, the reported closing sales price per Share on NASDAQ during normal trading hours was $94.54 per Share. The Offer Price represents an approximately 64.7% premium over the February 28, 2020 closing stock price.

        Forty Seven has never paid dividends on its common stock. In Forty Seven's Annual Report on Form 10-K for the fiscal year ended December 31, 2018, Forty Seven had indicated that it would continue to retain its future earnings for the development and growth of its business. Additionally, under the terms of the Merger Agreement, Forty Seven is not permitted to declare or pay any dividends on or make other distributions in respect of any of its capital stock. See Section 14—"Dividends and Distributions." Stockholders are urged to obtain a current market quotation for the Shares.

7.     Possible Effects of the Offer on the Market for the Shares; NASDAQ Listing; Exchange Act Registration and Margin Regulations.

        Possible Effects of the Offer on the Market for the Shares.    The purchase of Shares pursuant to the Offer will reduce the number of Shares that might otherwise trade publicly and could adversely affect the liquidity and market value of the remaining Shares held by the public. The purchase of Shares pursuant to the Offer can also be expected to reduce the number of holders of Shares. We cannot predict whether the reduction in the number of Shares that might otherwise trade publicly would have an adverse or beneficial effect on the market price or marketability of the Shares or whether it would cause future market prices to be greater or less than the Offer Price.

19

        NASDAQ Listing.    Depending upon the number of Shares purchased pursuant to the Offer, the Shares may no longer meet the requirements for continued listing on the NASDAQ. According to the published guidelines of The Nasdaq Stock Market, LLC, NASDAQ would consider disqualifying the Shares for listing on NASDAQ if, among other possible grounds, (a) the total number of holders of record and holders of beneficial interest, taken together, in the Shares falls below 400, (b) the bid price for a Share over a 30 consecutive business day period is less than $1.00, (c)(i) Forty Seven has stockholders' equity of less than $10 million, the number of publicly held Shares falls below 750,000, the market value of publicly held Shares over a 30 consecutive business day period is less than $5 million or there are fewer than two active and registered market makers in the Shares over a ten consecutive business day period, (ii) the number of publicly held Shares falls below 1,100,000, the market value of publicly held Shares over a 30 consecutive business day period is less than $15 million, there are fewer than four active and registered market makers in the Shares over a ten consecutive business day period, or the market value of Forty Seven's listed securities is less than $50 million over a ten consecutive business day period or (iii) the number of publicly held shares falls below 1,100,000, the market value of publicly held Shares over a 30 consecutive business day period is less than $15 million, there are fewer than four active and registered market makers in the Shares over a ten consecutive business day period, or Forty Seven's total assets and total revenue is less than $50 million each for the most recently completed fiscal year (or in two of the last three fiscal years). Shares held by officers or directors of Forty Seven, or by any beneficial owner of more than 10 percent of the Shares, will not be considered as being publicly held for this purpose. According to Forty Seven, there were, as of February 29, 2020, approximately 48,145,009 Shares issued and outstanding. If, as a result of the purchase of Shares pursuant to the Offer or otherwise, the Shares are delisted from NASDAQ, the market for Shares will be adversely affected.

        If NASDAQ were to delist the Shares, it is possible that the Shares would continue to trade on other securities exchanges or in the over-the-counter market and that price or other quotations for the Shares would be reported by other sources. The extent of the public market for such Shares and the availability of such quotations would depend, however, upon such factors as the number of stockholders and the aggregate market value of such securities remaining at such time, the interest in maintaining a market in the Shares on the part of securities firms, the possible termination of registration under the Exchange Act as described below, and other factors. We cannot predict whether the reduction in the number of Shares that might otherwise trade publicly would have an adverse or beneficial effect on the market price for or marketability of the Shares or whether it would cause future market prices to be greater or less than the Offer Price.

        Trading in the Shares will cease upon consummation of the Merger if trading has not ceased earlier as discussed above.

        Exchange Act Registration.    The Shares currently are registered under the Exchange Act. The purchase of the Shares pursuant to the Offer may result in the Shares becoming eligible for deregistration under the Exchange Act. Registration of the Shares may be terminated by Forty Seven upon application to the SEC if the outstanding Shares are not listed on a "national securities exchange" and if there are fewer than 300 holders of record of Shares.

        We intend to seek to cause Forty Seven to apply for termination of registration of the Shares as soon as possible after consummation of the Offer if the requirements for termination of registration are met. Termination of registration of the Shares under the Exchange Act would reduce the information required to be furnished by Forty Seven to its stockholders and to the SEC and would make certain provisions of the Exchange Act (such as the short-swing profit recovery provisions of Section 16(b), the requirement of furnishing a proxy statement or information statement in connection with stockholders' meetings or actions in lieu of a stockholders' meeting pursuant to Sections 14(a) and 14(c) under the Exchange Act and the related requirement of furnishing an annual report to stockholders) no longer applicable with respect to the Shares. In addition, if the Shares are no longer registered under the

20

Exchange Act, the requirements of Rule 13e-3 under the Exchange Act with respect to "going private" transactions would no longer be applicable to Forty Seven. Furthermore, the ability of "affiliates" of Forty Seven and persons holding "restricted securities" of Forty Seven to dispose of such securities pursuant to Rule 144 under the Securities Act of 1933, as amended, may be impaired or eliminated. If registration of the Shares under the Exchange Act were terminated, the Shares would no longer be eligible for continued inclusion on the Board of Governors' of the Federal Reserve System (the "Federal Reserve Board's") list of "margin securities" or eligible for stock exchange listing.

        If registration of the Shares is not terminated prior to the Merger, then the registration of the Shares under the Exchange Act will be terminated following completion of the Merger.

        Margin Regulations.    The Shares are currently "margin securities" under the regulations of the Federal Reserve Board, which has the effect, among other things, of allowing brokers to extend credit using such Shares as collateral. Depending upon factors similar to those described above regarding listing and market quotations, following the Offer, the Shares may no longer constitute "margin securities" for the purposes of the margin regulations of the Federal Reserve Board, in which event the Shares would be ineligible as collateral for margin loans made by brokers.

8.     Certain Information Concerning Forty Seven.

        The following description of Forty Seven and its business was taken from the shelf registration statement on Form S-3 (File No. 333-235877) which was automatically effective upon filing with the SEC on January 10, 2020 (as supplemented), and is qualified in its entirety by reference to such shelf registration statement.

        Forty Seven is a clinical-stage immuno-oncology company focused on developing novel therapies to activate macrophages in the fight against cancer. Forty Seven was founded based on the insight that blocking CD47, a key signaling molecule that is overexpressed on cancer cells, renders tumors susceptible to macrophages. By harnessing macrophages, Forty Seven believes that its lead product candidate, magrolimab (formerly known as 5F9), can transform the treatment of cancer.

        Forty Seven is a Delaware corporation incorporated in October 2014. Forty Seven's corporate headquarters are located at 1490 O'Brien Drive, Suite A, Menlo Park, California 94025. Forty Seven's telephone number at such corporate headquarters is (650) 352-4150.

        Available Information.    Forty Seven is subject to the information and reporting requirements of the Exchange Act and in accordance therewith is obligated to file reports and other information with the SEC relating to its business, financial condition and other matters. Certain information, as of particular dates, concerning Forty Seven's business, principal physical properties, capital structure, material pending litigation, operating results, financial condition, directors and officers (including their remuneration and stock options granted to them), the principal holders of Forty Seven's securities, any material interests of such persons in transactions with Forty Seven, and other matters is required to be disclosed in proxy statements and periodic reports distributed to Forty Seven's stockholders and filed with the SEC. Copies may be obtained by mail, upon payment of the SEC's customary charges, by writing to its principal office at 100 F Street, NE, Washington, DC 20549. The SEC also maintains an Internet website that contains reports, proxy statements and other information about issuers, such as Forty Seven, who file electronically with the SEC. The address of that site is http://www.sec.gov. Forty Seven also maintains an Internet website at http://www.fortyseveninc.com. The information contained in, accessible from or connected to Forty Seven's website is not incorporated into, or otherwise a part of, this Offer to Purchase or any of Forty Seven's filings with the SEC. The website addresses referred to in this paragraph are inactive text references and are not intended to be actual links to the websites.

        Sources of Information.    Except as otherwise set forth herein, the information concerning Forty Seven contained in this Offer to Purchase has been based upon publicly available documents and

21

records on file with the SEC, other public sources and information provided by Forty Seven. Although we have no knowledge that any such information contains any misstatements or omissions, none of Parent, Purchaser or any of their respective affiliates or assigns, the Information Agent or the Depositary assumes responsibility for the accuracy or completeness of the information concerning Forty Seven contained in such documents and records or for any failure by Forty Seven to disclose events which may have occurred or may affect the significance or accuracy of any such information.

9.     Certain Information Concerning Parent and Purchaser.

        General.    Purchaser is a Delaware corporation with its principal offices located at c/o Gilead Sciences, Inc., 333 Lakeside Drive, Foster City, California 94404. The telephone number of Purchaser is 650-574-3000. Purchaser is a wholly owned subsidiary of Parent. Purchaser was formed for the purpose of making a tender offer for all of the Shares of Forty Seven and has not engaged, and does not expect to engage, in any business other than in connection with the Offer and the Merger.

        Parent is a Delaware corporation with its principal offices located at 333 Lakeside Drive, Foster City, California 94404. The telephone number of Parent is 650-574-3000. Parent is a research-based biopharmaceutical company that discovers, develops and commercializes innovative medicines in areas of unmet medical need. Parent's primary areas of focus include viral diseases, inflammatory and fibrotic diseases and oncology.

        The name, citizenship, business address, business phone number, present principal occupation or employment and past material occupation, positions, offices or employment for at least the last five years for each director and each of the executive officers of Parent and Purchaser and certain other information are set forth in Schedule A hereto.

        During the last five years, none of Parent or Purchaser or, to the best knowledge of Parent and Purchaser, any of the persons listed in Schedule A hereto (i) has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) was a party to any judicial or administrative proceeding (except for matters that were dismissed without sanction or settlement) that resulted in a judgment, decree or final order enjoining the person from future violations of, or prohibiting activities subject to, federal or state securities laws, or a finding of any violation of such laws.

        Except as otherwise described in this Offer to Purchase, (i) none of Parent, Purchaser, any majority-owned subsidiary of Parent or Purchaser or, to the best knowledge of Parent and Purchaser, any of the persons listed in Schedule A hereto or any associate or any of the persons so listed beneficially owns or has any right to acquire, directly or indirectly, any Shares and (ii) none of Parent, Purchaser or, to the best knowledge of Parent and Purchaser, any of the persons or entities referred to above nor any director, executive officer or subsidiary of any of the foregoing has effected any transaction in the Shares during the past 60 days.

        Except as otherwise described in this Offer to Purchase, none of Parent, Purchaser or, to the best knowledge of Parent and Purchaser, any of the persons listed in Schedule A hereto, has any contract, arrangement, understanding or relationship with any other person with respect to any securities of Forty Seven, including, but not limited to, any contract, arrangement, understanding or relationship concerning the transfer or voting of such securities, finder's fees, joint ventures, loan or option arrangements, puts or calls, guarantees of loans, guarantees against loss, guarantees of profits, division of profits or loss or the giving or withholding of proxies.

22

        Except as set forth in this Offer to Purchase, none of Parent, Purchaser or, to the best knowledge of Parent and Purchaser, any of the persons listed on Schedule A hereto, has had any business relationship or transaction with Forty Seven or any of its executive officers, directors or affiliates that is required to be reported under the rules and regulations of the SEC applicable to the Offer. Except as set forth in this Offer to Purchase, there have been no contacts, negotiations or transactions between Parent or any of its subsidiaries or, to the best knowledge of Parent, any of the persons listed in Schedule A hereto, on the one hand, and Forty Seven or its affiliates, on the other hand, concerning a merger, consolidation or acquisition, tender offer or other acquisition of securities, an election of directors or a sale or other transfer of a material amount of assets during the past two years.

        Available Information.    Pursuant to Rule 14d-3 under the Exchange Act, Parent and Purchaser filed with the SEC a Tender Offer Statement on Schedule TO (the "Schedule TO"), of which this Offer to Purchase forms a part, and exhibits to the Schedule TO. Copies of the Schedule TO and the exhibits thereto, and reports, proxy statements and other information may be obtained by mail, upon payment of the SEC's customary charges, by writing to its principal office at 100 F Street, NE, Washington, DC 20549. Parent filings are also available to the public on the SEC's website (http://www.sec.gov).

10.   Background of the Offer; Contacts with Forty Seven.

        Background of the Offer and the Merger; Past Contacts or Negotiations between Parent and Forty Seven. The following is a description of contacts between representatives of Parent or Purchaser with representatives of Forty Seven that resulted in the execution of the Merger Agreement and the agreements related to the Offer. For a review of Forty Seven's activities relating to these contacts, please refer to Forty Seven's Schedule 14D-9 being mailed to stockholders with this Offer to Purchase.

Background of the Offer and the Merger

        The information set forth below regarding Forty Seven was provided by Forty Seven, and none of Parent, Purchaser or any of its affiliates or representatives takes any responsibility for the accuracy or completeness of any information regarding meetings or discussions in which Parent or its affiliates or representatives did not participate. The following contains a description of material contacts between representatives of Parent or Purchaser and representatives of Forty Seven that resulted in the execution of the Merger Agreement and the agreements related to the Offer. For a review of Forty Seven's activities relating to these contacts, please refer to Forty Seven's Schedule 14D-9 that will be filed with the SEC and mailed to all Forty Seven stockholders with this Offer to Purchase.

        The board of directors of Parent (the "Parent Board") as well as Parent's executive management regularly evaluates various strategies to improve its competitive position and enhance value for Parent stockholders, including opportunities for acquisitions of other companies or their assets. Parent also meets with potential partners and acquisition targets on a regular basis to understand these companies' businesses and evaluate the potential opportunities.

        On December 9, 2019, Forty Seven announced updated clinical data from its trial evaluating magrolimab in combination with azacitidine for the treatment of myelodysplastic syndrome and acute myeloid leukemia. The new results showed the combination of magrolimab and azacitidine to be highly active and well tolerated in relevant patients.

        On December 19, 2019, members of Parent's senior leadership, including Daniel O'Day, Chief Executive Officer of Parent, Jeremy Bender, Ph.D., Vice President, Corporate Development of Parent, Merdad Parsey, M.D., Ph.D., Chief Medical Officer of Parent, and Andrew Dickinson, Chief Financial Officer of Parent met at Parent's headquarters in Foster City, California to discuss Parent's broader oncology strategy and related strategic transaction opportunities. Parent's senior leadership determined

23

that Forty Seven represented a strong potential target for a strategic transaction and determined that engaging with Forty Seven would be a high priority for Parent.

        On December 20, 2019, Dr. Bender spoke with Craig Gibbs, Ph.D., Chief Business Officer of Forty Seven to discuss Parent's interest in magrolimab. Dr. Bender and Dr. Gibbs agreed that representatives of Parent and Forty Seven would meet in January 2020 for an overview of magrolimab. Dr. Bender and Dr. Gibbs agreed to put in place a confidentiality agreement to facilitate discussions regarding magrolimab between Parent and Forty Seven.

        Also on December 20, 2019, Parent retained J.P. Morgan Securities LLC ("J.P. Morgan") as its financial advisor to advise Parent on a potential acquisition of Forty Seven.

        On January 7, 2020, Parent and Forty Seven executed the Confidential Disclosure Agreement.

        On January 8, 2020, Dr. Bender, Dr. Parsey, and William Lee, Ph.D., Executive Vice President, Research of Parent met with Dr. Gibbs, Mark McCamish, M.D., Ph.D., President and Chief Executive Officer of Forty Seven, and Chris Takimoto, M.D., Ph.D., F.A.C.P., Chief Medical Officer of Forty Seven at Parent's headquarters in Foster City, California. At the meeting, representatives of Forty Seven provided Parent with an in-depth review of the magrolimab clinical program and key data.

        On January 11, 2020, Forty Seven provided Parent access to a virtual data room containing limited information regarding magrolimab.

        On January 24, 2020, Dr. Bender spoke with Dr. Gibbs and indicated Parent's continued interest in magrolimab. Dr. Bender also delivered an update on Parent's diligence process.

        On January 28, 2020, Parent Board held a regularly-scheduled meeting. At the meeting, Parent Board discussed Parent's corporate development priorities, including updates on the recent discussions with Forty Seven. Parent Board approved Parent's executive leadership continuing to pursue a strategic transaction involving Forty Seven.

        Also on January 28, 2020, Parent retained Citigroup Global Markets Inc. ("Citi") as its joint financial advisor to advise Parent on a potential acquisition of Forty Seven.

        On January 31, 2020 representatives of Parent and Forty Seven's Chemistry, Manufacturing and Controls teams spoke in connection with Parent's continued diligence of Forty Seven and magrolimab.

        On January 31, 2020, Dr. Bender conveyed to Dr. Gibbs, that Parent was making good progress on its due diligence review of Forty Seven's data and that, based on its evaluation of the strategic fit of the two companies, it wished to transition the then ongoing partnership discussions to discussions about a potential strategic transaction with Forty Seven and that in the coming days, Parent would be submitting an offer to acquire Forty Seven.

        On February 6, 2020, Parent had a meeting of its standing Transaction Committee (the "Parent Transaction Committee") to discuss Forty Seven. At the meeting, members of Parent's senior leadership provided the Parent Transaction Committee an overview of Forty Seven, including its clinical programs; Parent's interactions with Forty Seven prior to February 6, 2020 and discussed Parent's preliminary assessment of and valuation analysis on Forty Seven. After discussion, the Parent Transaction Committee authorized management to submit a non-binding acquisition proposal to Forty Seven to acquire all of the outstanding shares of Forty Seven.

        On February 9, 2020, Dr. Bender contacted Dr. Gibbs to communicate that Mr. O'Day would like to meet with Dr. McCamish to discuss how Parent and Forty Seven could work together.

        On February 10, 2020, Mr. O'Day and Dr. McCamish met at a restaurant in Palo Alto, California to discuss Parent's interest in Forty Seven. Mr. O'Day and Dr. McCamish discussed their passion and vision for oncology and how the combination of Parent and Forty Seven could maximize the potential

24

for magrolimab. During the meeting, Mr. O'Day expressed interest in a potential acquisition of Forty Seven and indicated that Parent would submit a written proposal later that day to all of the outstanding shares of Forty Seven.

        Later that day, Mr. O'Day, on behalf of Parent, sent Dr. McCamish a non-binding indication of interest to acquire all of the outstanding shares of Forty Seven at a price of $57.50 per Share in cash (the "February 10 Proposal"). The proposal indicated that business diligence was substantially complete and that the remaining diligence would be largely confirmatory. The proposal also confirmed Parent's willingness to execute a definitive acquisition agreement within a few weeks.

        On February 11, 2020, Dr. Bender contacted Dr. Gibbs to discuss the February 10 Proposal. Dr. Gibbs did not provide any feedback on Parent's proposal or indicate any next-steps regarding the timing of Forty Seven's response.

        On February 18, 2020, Dr. McCamish contacted Mr. O'Day to propose they meet to discuss Parent's interest in Forty Seven and the February 10 Proposal. Later that evening, Dr. McCamish and Mr. O'Day met at a restaurant in Redwood City, California and discussed their continued interest in finding ways for Parent and Forty Seven to work together. Dr. McCamish conveyed to Mr. O'Day that the February 10 Proposal was not sufficient and that a substantial improvement in offer terms would be required in order for the parties to continue discussions.

        On February 19, 2020, representatives of Centerview contacted Mr. Dickinson and informed him that the board of directors of Forty Seven (the "Forty Seven Board") had determined that the February 10 Proposal was not sufficient and that Parent would need to improve its proposal. Representatives of Centerview and Mr. Dickinson discussed that additional diligence access and documents from Forty Seven could assist Parent in submitting an increased proposal.

        On February 20, 2020, representatives of Centerview, Citi and J.P. Morgan discussed the February 10 Proposal and next steps similar to what was discussed by Centerview and Mr. Dickinson the previous day.

        Also on February 20, 2020, Mr. O'Day called Dr. McCamish to acknowledge Forty Seven's feedback that Parent needed to increase its offer price. Mr. O'Day explained that Parent would be sending Forty Seven a list of additional key due diligence questions that Parent viewed as critical to such increased price. Later that day, Citi and J.P. Morgan followed up by email with Centerview to share the list of key due diligence questions.

        On February 21, 2020, Forty Seven uploaded additional confidential, non-public clinical data to the virtual data room in response to Parent's additional diligence questions.

        On February 22, 2020, J.P. Morgan, Citi and Skadden, Arps, Slate, Meagher & Flom LLP, outside counsel to Parent ("Skadden") were granted access to Forty Seven's virtual data room.

        Later that day, representatives of J.P. Morgan and Citi contacted Centerview to share additional follow-up questions from Parent in response to the new material that had been uploaded into the virtual data room. During this call, J.P. Morgan and Citi proposed that representatives of Parent and Forty Seven discuss responses to these questions the following morning.

        On February 23, 2020, representatives of Parent and Forty Seven's senior management, including Dr. Parsey, and Pankaj Bhargava, Vice President of Oncology Clinical Research of Parent, and Dr. Bender, Dr. McCamish, Mr. Takimoto, Mark Chao, Senior Vice President and Head of Clinical Development of Forty Seven and Dr. Gibbs met telephonically to discuss the additional clinical data regarding magrolimab that had been uploaded to the virtual data room. Representatives of Citi, J.P. Morgan and Centerview were also present.

25

        Also on February 23, 2020, Mr. O'Day called Dr. McCamish to thank his team for being available over the weekend for Parent's additional diligence questions and to let him know that a revised offer was forthcoming, together with an updated draft of the merger agreement. Mr. O'Day also reiterated Parent's willingness and eagerness to move quickly towards a signing. Following their discussion, Mr. O'Day sent Dr. McCamish a revised non-binding indication of interest to acquire all of the outstanding shares of Forty Seven for $64.50 per Share in cash (the "February 23 Proposal"). The February 23 Proposal represented a 12.2% increase from the February 10 Proposal. The proposal indicated Parent's willingness to move quickly towards the signing and announcement of a transaction on March 1, 2020 and was accompanied by a proposed form of merger agreement prepared by Skadden.

        On February 25, 2020, Mr. O'Day and Dr. McCamish spoke regarding the February 23 Proposal. Dr. McCamish indicated that the February 23 Proposal was insufficient and that Forty Seven would require an offer of at least $68.35 per Share in cash to continue moving forward with Parent's proposed transaction and on the timeframe Parent proposed in the February 23 Proposal.

        Later that day, Mr. O'Day contacted Dr. McCamish to communicate that he was willing to go back to the Parent Board to request approval to increase Parent's offer to $66 per Share in cash provided that Forty Seven agreed to work with Parent towards an announcement goal of March 2, 2020, before market open (the "February 25 Proposal").

        Also on February 25, 2020, Parent held a meeting of the Parent Transaction Committee to discuss Forty Seven. At the Parent Transaction Committee meeting, Parent management provided an update on Parent's due diligence review of Forty Seven, including an update on the valuation of Forty Seven based on Parent's additional due diligence.

        On the morning of February 27, 2020, Parent held a meeting of the Parent Board to provide an update regarding Parent's due diligence review of Forty Seven, including an updated valuation of Forty Seven based on Parent's due diligence review, and a summary of the key terms of the draft merger agreement.

        On February 27, 2020, during after-market hours, Bloomberg News, citing anonymous sources familiar with the matter, reported that Parent had approached Forty Seven with a takeover offer. Forty Seven's stock price rose in after-hours trading, closing at $48.79 per share on February 27, 2020 and opening at $58.35 per share on February 28, 2020, reaching a high of $65.00 per share during the day on February 28, 2020.

        Also on February 27, 2020, representatives of J.P. Morgan, Citi and Centerview had a conversation where Centerview conveyed that Forty Seven had received a competing proposal that was materially ahead of the February 25 Proposal and advised that Forty Seven was expecting to hold a meeting of the Forty Seven Board on the afternoon of February 28, and that Parent should submit an improved bid prior to the meeting. During the conversation, Centerview communicated to J.P. Morgan and Citi that Parent would need to make a meaningful move substantially into the $70s in order to remain competitive. In response to the communications between representatives of Parent and Forty Seven, Parent held a meeting of the Parent Transaction Committee to discuss recent developments, including news of the competing offer. The Parent Transaction Committee agreed to reconvene on the morning of February 28 to further discuss the Forty Seven transaction.

        Also on February 27, 2020, Mr. O'Day and Dr. McCamish spoke to further discuss Parent and Forty Seven's process in light of the competing proposal.

        That same day, Parent, Skadden, J.P. Morgan and Citi were granted access to a second data room, in addition to the existing data room utilized for partnering discussions. The second data room contained significantly more information than the data room prior to that date, access to which had

26

been granted to parties interested in partnership discussions, and included documents that were responsive to many of Parent's due diligence requests.

        Later the same day, Cooley LLP, outside counsel to Forty Seven ("Cooley") sent a revised draft of the merger agreement to Skadden.

        Over the course of February 27, 2020 through February 29, 2020, additional information regarding Forty Seven's business and operations was made available in the corporate data room, including documents that were responsive to Parent's due diligence requests.

        On the morning of February 28, 2020, representatives of Parent and Forty Seven conducted two separate due diligence calls. Parent and Forty Seven's clinical and regulatory teams had a call where they discussed certain clinical data regarding Forty Seven's clinical trial of magrolimab. Parent and Forty Seven's legal and intellectual property teams had a call where they discussed certain legal and intellectual property items regarding Forty Seven.

        On the morning of February 28, 2020, Parent reconvened the Parent Transaction Committee to provide an updated valuation of Forty Seven. The Parent Transaction Committee approved a proposal to seek written consent from Parent Board to make an improved offer to Forty Seven. Later that day, Parent Board executed an action by written consent authorizing the Parent Transaction Committee and certain executive officers of Parent to make an improved offer to Forty Seven. J.P. Morgan and Citi, on behalf of Parent, then sent Centerview a revised non-binding indication of interest from Parent to acquire all of the outstanding shares of Forty Seven for $77.00 per Share in cash and confirming Parent's ability to sign a merger agreement with Forty Seven in a matter of hours and no later than Sunday, March 1 (the "February 28 Proposal"). The February 28 Proposal represented a 19.4% increase from the February 23 Proposal and a 33.9% increase from the February 10 Proposal.

        That same day, Skadden sent a revised draft of the merger agreement to Cooley.

        Also on February 28, 2020, representatives of J.P. Morgan and Citi communicated to Centerview that Parent had completed their due diligence review of Forty Seven.

        Also on February 28, 2020, following the Forty Seven Board meeting, Centerview had a discussion with J.P. Morgan and Citi where Centerview conveyed that the February 28 Proposal was still behind the other proposal that Forty Seven had received on offer price. During such discussions, Citi and J.P. Morgan confirmed that Parent was prepared to submit an improved proposal and that Parent could be in a position to sign a merger agreement as early as that evening and by no later than Sunday, March 1. Centerview indicated that final bids would be due to Forty Seven by March 1, 2020 at 10:00 am Pacific time, after which the Forty Seven Board would convene to determine the winning party. Following this, Centerview sent J.P. Morgan and Citi a process letter indicating that Parent was to submit its best and final offer to acquire Forty Seven by no later than 10:00 am Pacific time on March 1, 2020.

        Later that same day, Cooley sent Skadden a revised draft of the merger agreement and an initial draft of the confidential disclosure schedules to the merger agreement.

        On February 29, 2020, Parent held a meeting of the Parent Transaction Committee to provide an update on the recent discussions with Forty Seven, including Centerview's instructions to provide final offers on March 1, 2020 in advance of the Forty Seven Board meeting. The Parent Transaction Committee also reviewed an updated valuation analysis of Forty Seven and discussed potential bidding strategies for the March 1 bid deadline. The Parent Transaction Committee approved Parent submitting an additional bid to acquire Forty Seven.

        Also on February 29, 2020, Skadden sent a revised draft of the confidential disclosure schedules to the merger agreement to Cooley.

27

        Later that day, Skadden and Cooley had a call to discuss certain open points in the merger agreement. Following the conversation with Skadden, Cooley sent Skadden revised drafts of both the merger agreement and the confidential disclosure schedules.

        Also on February 29, 2020, Mr. O'Day and Dr. McCamish spoke to further discuss process expectations in advance of the March 1 bid deadline, and on the following morning, communicated to confirm the same.

        Also on February 29, 2020 and early in the day on March 1, 2020 representatives of J.P. Morgan, Citi, and Centerview discussed process expectations for the submission of best and final offers, and Centerview informed J.P. Morgan and Citi that in order to avoid another round of bidding, either party would need to submit a bid on March 1 that was clearly superior to the other party's proposal.

        On the morning of March 1, 2020, Mr. O'Day spoke with Ian Clark, a director of Forty Seven, to express Parent's conviction in reaching a deal with Forty Seven.

        Also on the morning of March 1, 2020, Parent held a meeting of the Parent Board to update the Parent Board on negotiations with Forty Seven. Parent Board authorized the Parent Transaction Committee and certain executive officers of Parent to make an improved offer to Forty Seven later that day, which would represent Parent's best and final offer. Following the Parent Board meeting, J.P. Morgan and Citi, on behalf of Parent, submitted a final non-binding indication of interest to Forty Seven proposing to acquire all of the outstanding shares of Forty Seven at a price of $95.50 per Share in cash (the "March 1 Proposal"). The March 1 Proposal represented a 24.0% increase from the February 28 Proposal and a 66.1% increase from the February 10 Proposal.

        Later that day, Skadden and Cooley indicated that negotiations regarding the merger agreement and the confidential disclosure schedules were completed.

        At 1:00 pm Pacific time on March 1, 2020, the Forty Seven Board met to discuss the offers that had been received, including the March 1 Proposal. At the Forty Seven Board meeting, the Forty Seven Board unanimously (i) determined that the Merger Agreement and the Transactions, including the Offer and the Merger, are fair to, and in the best interest of, Forty Seven and its stockholders, (ii) declared it advisable to enter into the Merger Agreement, (iii) approved the execution, delivery and performance by Forty Seven of the Merger Agreement and the consummation of the Transactions, including the Offer and the Merger, (iv) resolved that the Merger shall be effected under Section 251(h) of the DGCL, and (v) resolved to recommend that the stockholders of Forty Seven accept the Offer and tender their Shares to Purchaser pursuant to the Offer.

        Following the Forty Seven Board meeting, representatives of Forty Seven indicated to Parent and Parent's advisors that Forty Seven had unanimously accepted the March 1 Proposal and approved the merger agreement and confidential disclosure schedules between Forty Seven and Parent. Dr. McCamish called Mr. O'Day directly to deliver to Mr. O'Day the news that the March 1 Proposal had been accepted.

        Soon after the meeting on the same day, Parent, Purchaser, and Forty Seven executed the Merger Agreement. Early the next morning, on March 2, 2020, Parent and Forty Seven issued a joint press release announcing the execution of the Merger Agreement.

        On March 10, 2020, Purchaser commenced the Offer and filed this Schedule TO-T.

28

11.   Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements.

Purpose of the Offer and Plans for Forty Seven.

        Purpose of the Offer.    The purpose of the Offer and the Merger is for Parent and its affiliates, through Purchaser, to acquire control of, and the entire equity interest in, Forty Seven. Pursuant to the Merger, Parent will acquire all of the stock of Forty Seven not purchased pursuant to the Offer or otherwise. Stockholders of Forty Seven who sell their Shares in the Offer will cease to have any equity interest in Forty Seven or any right to participate in its earnings and future growth.

        Merger Without a Stockholder Vote.    If the Offer is consummated, we do not anticipate seeking the approval of Forty Seven's remaining public stockholders before effecting the Merger. Section 251(h) of the DGCL provides that following consummation of a successful tender offer for a public corporation, and subject to certain statutory provisions, if the acquiring corporation owns at least the amount of shares of each class of stock of the target corporation that would otherwise be required to adopt a merger agreement for the target corporation, and the other stockholders receive the same consideration for their stock in the merger as was payable in the tender offer, the acquiring corporation can effect a merger without the action of the other stockholders of the target corporation. Accordingly, if we consummate the Offer, we intend to effect the closing of the Merger (the "Closing") without a vote of the stockholders of Forty Seven in accordance with Section 251(h) of the DGCL, upon the terms and subject to the satisfaction or waiver of the conditions to the Merger, as soon as practicable after the consummation of the Offer. Accordingly, we do not expect there to be a significant period of time between the consummation of the Offer and the consummation of the Merger.

        Plans for Forty Seven.    At the Effective Time, the certificate of incorporation of Forty Seven will be amended and restated in its entirety pursuant to the terms of the Merger Agreement. As of the Effective Time, the bylaws of the Surviving Corporation will be amended and restated to conform to the bylaws of Purchaser as in effect immediately prior to the Effective Time, except that references to the name of Purchaser will be replaced by references to the name of the Surviving Corporation. Purchaser's directors and officers immediately prior to the Effective Time will be the initial directors and officers of the Surviving Corporation until their respective successors are duly elected and qualified, or their earlier death, resignation or removal. See "Summary of the Merger Agreement—Board of Directors and Officers" below.

        Parent and Purchaser are conducting a detailed review of Forty Seven and its assets, corporate structure, capitalization, operations, properties, policies, management and personnel, and will consider which changes would be desirable in light of the circumstances that exist upon completion of the Offer and the Merger. Parent and Purchaser will continue to evaluate the business and operations of Forty Seven during the pendency of the Offer and after the consummation of the Offer and the Merger and will take such actions as they deem appropriate under the circumstances then existing. Thereafter, Parent intends to review such information as part of a comprehensive review of Forty Seven's business, operations, capitalization and management with a view to optimizing development of Forty Seven's potential in conjunction with Forty Seven's or Parent's existing businesses. Possible changes could include changes in Forty Seven's business, corporate structure, certificate of incorporation, bylaws, capitalization, board of directors and management. Plans may change based on further analysis and Parent, Purchaser and, after completion of the Offer and the Merger, the reconstituted Forty Seven Board reserves the right to change their plans and intentions at any time, as deemed appropriate.

        Except as disclosed in this Offer to Purchase, Parent and Purchaser do not have any present plan or proposal that would result in the acquisition by any person of additional securities of Forty Seven, the disposition of securities of Forty Seven, an extraordinary corporate transaction, such as a merger, reorganization or liquidation, involving Forty Seven or the sale or transfer of a material amount of assets of Forty Seven.

29

Summary of the Merger Agreement and Certain Other Agreements.

        The following summary of certain provisions of the Merger Agreement and all other provisions of the Merger Agreement discussed herein are qualified by reference to the Merger Agreement itself, which is incorporated herein by reference. We have filed a copy of the Merger Agreement as Exhibit (d)(1) to the Schedule TO. The Merger Agreement may be examined and copies may be obtained at the places and in the manner set forth in Section 9—"Certain Information Concerning Parent and Purchaser." Stockholders and other interested parties should read the Merger Agreement for a more complete description of the provisions summarized below. Capitalized terms used herein and not otherwise defined have the respective meanings set forth in the Merger Agreement.

        The Merger Agreement has been filed with the SEC and incorporated by reference herein to provide investors and stockholders with information regarding the terms of the Offer and the Merger. It is not intended to provide any other factual information about Parent, Purchaser or Forty Seven. The representations, warranties and covenants contained in the Merger Agreement were made only as of specified dates for the purposes of such agreement, were (except as expressly set forth therein) solely for the benefit of the parties to such agreement and may be subject to qualifications and limitations agreed upon by such parties. In particular, in reviewing the representations, warranties and covenants contained in the Merger Agreement and any description thereof contained or incorporated by reference herein, it is important to bear in mind that such representations, warranties and covenants were negotiated with the principal purpose of allocating risk among the parties, rather than establishing matters as facts. Such representations, warranties and covenants may also be subject to a contractual standard of materiality different from those generally applicable to stockholders and reports and documents filed with the SEC, and in some cases were qualified by disclosures set forth in confidential disclosure schedules that were provided by Forty Seven to Parent and Purchaser but not filed with the SEC as part of the Merger Agreement. Investors and stockholders are not third-party beneficiaries under the Merger Agreement, except with respect to their right to receive the Offer Price following the Offer Acceptance Time or to receive the Merger Consideration (as defined below). Accordingly, investors and stockholders should not rely on such representations, warranties and covenants as characterizations of the actual state of facts or circumstances described therein. Information concerning the subject matter of such representations, warranties and covenants, which do not purport to be accurate as of the date of this Offer to Purchase, may have changed since the date of the Merger Agreement, which subsequent information may or may not be fully reflected in the parties' public disclosures.

        The Offer.    The Merger Agreement provides that Purchaser will commence the Offer no later than March 13, 2020. Purchaser's obligation to accept for payment and pay for Shares validly tendered in the Offer is subject to the satisfaction of the Minimum Tender Condition and the other Offer Conditions that are described in Section 13—"Conditions of the Offer." Subject to the satisfaction of the Minimum Tender Condition and the other Offer Conditions that are described in Section 13—"Conditions of the Offer," the Merger Agreement provides that Purchaser will, and Parent will cause Purchaser to, immediately after the applicable Expiration Date, as it may be extended pursuant to the terms of the Merger Agreement, irrevocably accept for payment all Shares tendered and not validly withdrawn pursuant to the Offer and, as promptly as practicable after the Offer Acceptance Time (and in any event within three (3) business days), pay for such Shares. The Offer will expire at one minute after 11:59 p.m., Eastern Time on April 6, 2020, unless we extend the Offer pursuant to the terms of the Merger Agreement.

        Purchaser expressly reserves the right to (i) increase the amount of cash constituting the Offer Price, (ii) waive any Offer Condition (to the extent permitted under applicable legal requirements) and (iii) make any other changes in the terms and conditions of the Offer that are not inconsistent with the

30

terms of the Merger Agreement, except that Forty Seven's prior written approval is required for Parent or Purchaser to:

        The Merger Agreement contains provisions to govern the circumstances under which Purchaser is required to, and Parent is required to cause Purchaser to, extend the Offer. Specifically, the Merger Agreement provides that:

        However, Purchaser is not required to extend the Offer beyond the earlier to occur of the valid termination of the Merger Agreement in accordance with its terms and the End Date (defined in the Merger Agreement as June 1, 2020, or as late as September 1, 2020 in the event the End Date has been extended as provided in the Merger Agreement) (such earlier occurrence, the "Extension Deadline") and may not extend the Offer beyond the Extension Deadline without Forty Seven's prior written consent.

        Upon any valid termination of the Merger Agreement, Purchaser has agreed that it will (and Parent will cause Purchaser to) immediately, irrevocably and unconditionally terminate the Offer and Purchaser will not acquire any Shares pursuant to the Offer.

        The Merger.    The Merger Agreement provides that, following completion of the Offer and subject to the terms and conditions of the Merger Agreement, and in accordance with the DGCL, at the Effective Time, Purchaser will be merged with and into Forty Seven, the separate existence of Purchaser will cease, and Forty Seven will continue as the Surviving Corporation in the Merger. The Merger will be effected under Section 251(h) of the DGCL. Accordingly, Parent, Purchaser and Forty Seven have agreed to take all necessary action to cause the Merger to become effective as soon as practicable following (but in any event on the same date as) the Offer Acceptance Time without a vote of Forty Seven's stockholders in accordance with Section 251(h) of the DGCL, upon the terms and subject to the satisfaction or waiver of the conditions to the Merger.

31

        As of the Effective Time, the certificate of incorporation of Forty Seven will, by virtue of the Merger and without any further action, be amended and restated in its entirety as set forth on Annex II to the Merger Agreement and, as so amended and restated, will be the certificate of incorporation of the Surviving Corporation.

        As of the Effective Time, the bylaws of the Surviving Corporation will be amended and restated to conform to the bylaws of Purchaser as in effect immediately prior to the Effective Time, except that references to the name of Purchaser will be replaced by references to the name of the Surviving Corporation.

        The obligations of Forty Seven, Parent and Purchaser to complete the Merger are subject to the satisfaction or, to the extent permitted by applicable legal requirements, waiver as of the Closing by each of the parties of the following conditions:

        Board of Directors and Officers.    As of the Effective Time, the board of directors and officers of the Surviving Corporation will be the respective individuals who served as the directors and officers of Purchaser as of immediately prior to the Effective Time, until their respective successors have been duly elected and qualified, or until their earlier death, resignation or removal. Each director of Forty Seven immediately prior to the Effective Time will execute and deliver a letter effectuating his or her resignation as a member of the Forty Seven Board to be effective as of the Effective Time.

        Conversion of Capital Stock at the Effective Time.    Shares outstanding immediately prior to the Effective Time (other than Shares held by Forty Seven (or held in the treasury of Forty Seven) or Shares held by Parent, Purchaser or any other direct or indirect wholly-owned subsidiary of Parent, which will be canceled and retired and cease to exist without consideration or payment; and Shares held by a holder who properly exercises and perfects appraisal rights in accordance with Section 262 of the DGCL with respect to such Shares), including any Shares subject to vesting or employment based forfeiture conditions ("Restricted Shares") will be converted at the Effective Time into the right to receive $95.50 per Share, net to the seller in cash, in each case, without interest, without regard to any vesting or employment based forfeiture conditions which were applicable to the Restricted Shares and subject to any withholding of taxes (collectively, the "Merger Consideration").

        Each share of Purchaser's common stock outstanding immediately prior to the Effective Time will be converted into one share of common stock of the Surviving Corporation.

        Promptly after (and in any event no later than the third (3rd) business day after) the Offer Acceptance Time, Parent will deposit, or will cause to be deposited, with Computershare Trust Company, N.A. (the "Paying Agent"), cash sufficient to make the payment of the aggregate Offer Price. On or prior to the closing date, Parent will deposit, or will cause to be deposited, with the Paying Agent cash sufficient to pay the aggregate Merger Consideration in the Merger.

        Treatment of Equity Awards.    Pursuant to the Merger Agreement, each option to purchase Shares (whether granted by Forty Seven pursuant to its equity plans, assumed by Forty Seven in connection with any merger, acquisition or similar transaction or otherwise issued or granted, each a "Company

32

Option") that is outstanding and unexercised, whether or not vested and which has a per share exercise price that is less than the Merger Consideration, will be cancelled and converted into the right to receive a cash payment equal to (i) the excess of (x) the Merger Consideration over (y) the exercise price payable per Share under such Company Option, multiplied by (ii) the total number of Shares subject to such Company Option immediately prior to the Effective Time.

        Representations and Warranties.    This summary of the Merger Agreement has been included to provide investors with information regarding its terms. It is not intended to provide any other factual information about Parent, Purchaser or Forty Seven, their respective businesses, or the actual conduct of their respective businesses during the period prior to the consummation of the Offer or the Merger. The Merger Agreement contains representations and warranties that are the product of negotiations among the parties thereto and made to, and solely for the benefit of, each other as of specified dates. The assertions embodied in those representations and warranties are subject to qualifications and limitations agreed to by the respective parties and are also qualified in important part by confidential disclosure schedules delivered by Forty Seven to Parent in connection with the Merger Agreement. The representations and warranties were negotiated with the principal purpose of allocating risk among the parties to the agreements instead of establishing these matters as facts, and may be subject to standards of materiality applicable to the contracting parties that differ from those applicable to investors.

        In the Merger Agreement, Forty Seven has made representations and warranties to Parent and Purchaser with respect to, among other things:

33

        Some of the representations and warranties in the Merger Agreement made by Forty Seven are qualified as to "materiality" or "Material Adverse Effect." For purposes of the Merger Agreement, a "Material Adverse Effect" means any change, circumstance, condition, development, effect, event, occurrence or state of facts, which, individually or when taken together with all other events, occurrences, circumstances, changes, conditions, states of facts, developments or effects that have occurred in the applicable determination period for a Material Adverse Effect, has had or would reasonably be expected to have a material adverse effect on (a) the ability of Forty Seven to consummate the Offer and the Merger on or before the End Date or (b) the business, assets, financial condition or results of operations of Forty Seven, taken as a whole. The definition of "Material Adverse Effect" excludes the following from constituting or being taken into account in determining whether there has been, or would reasonably be expected to be a Material Adverse Effect for the purposes of clause (b) above:

34

        In the Merger Agreement, Parent and Purchaser have made representations and warranties to Forty Seven with respect to:

        Some of the representations and warranties in the Merger Agreement made by Parent and Purchaser are qualified as to "materiality" or the ability to consummate the transactions contemplated by the Merger Agreement.

        None of the representations and warranties of the parties to the Merger Agreement contained in the Merger Agreement or in any schedule, instrument or other document delivered pursuant to the Merger Agreement will survive the Effective Time.

        Access to Information.    From the date of the Merger Agreement until the earlier of the Effective Time and the termination of the Merger Agreement pursuant to its terms, upon reasonable advance notice, Forty Seven will provide Parent and Parent's officers, directors, employees, attorneys, accountants, investment bankers, consultants, agents, financial advisors and other advisors and representatives (collectively, "Representatives") reasonable access during Forty Seven's normal business hours to Forty Seven's Representatives, designated personnel and assets, and to all existing books, records, documents and information relating to Forty Seven, as Parent may reasonably request, and to

35

promptly provide all reasonably requested information regarding Forty Seven's business, in each case for any reasonable business purpose related to the consummation of the Transactions and subject to customary exceptions and limitations.

        Notice of Certain Events.    Forty Seven and Parent have agreed to promptly notify the other of (i) any notice or communication received by such party from any governmental body in connection with the Transactions or from any person alleging that the consent of such person may be required in connection with the Transactions; (ii) any legal proceeding commenced or, to any party's knowledge, threatened in writing, against such party or any of its subsidiaries or otherwise relating to, involving or affecting such party or any of its subsidiaries, in each case in connection with, arising from or otherwise relating to the Transactions; or (iii) any change, circumstance, condition, development, effect, event, occurrence or state of facts that has had or would reasonably be expected to have a Material Adverse Effect or Parent Material Adverse Effect, as applicable, or would reasonably be expected to make the satisfaction of any of the Offer Conditions impossible or unlikely.

        Conduct of Business Pending the Merger.    Forty Seven has agreed that, from the date of the Merger Agreement until the earlier of the Effective Time and the termination of the Merger Agreement pursuant to its terms, except as expressly provided by the Merger Agreement or required by applicable legal requirements or to the extent necessary to comply with any obligation under any contracts made available to Parent on or prior to the date of the Merger Agreement, as consented to in writing by Parent (which consent may not be unreasonably withheld, conditioned or delayed) or as disclosed prior to execution of the Merger Agreement in Forty Seven's confidential disclosure schedules, it will use commercially reasonable efforts to (i) conduct its business in the ordinary course consistent with past practice and (ii) preserve intact its material assets, properties, contracts, licenses and business organization and to preserve satisfactory business relationships with licensors, licensees, lessors, governmental bodies and others having material business dealings with Forty Seven. In addition, Forty Seven will not, among other things and subject to specified exceptions (including specified ordinary course exceptions):

36

37

        Filings, Consents and Approvals.    Each of Forty Seven, Parent and Purchaser has agreed to use its reasonable best efforts to take promptly any and all steps necessary to avoid or eliminate every impediment under any antitrust laws that may be asserted by any governmental body, so as to enable the closing to occur as promptly as practicable, but in no case later than the End Date, including providing as promptly as reasonably practicable and advisable all non-legally privileged information reasonably required by any governmental body pursuant to its evaluation of the Transactions under the HSR Act. Each of Forty Seven, Parent and Purchaser has also agreed to use reasonable best efforts to obtain from any governmental body all consents, approvals, authorizations or orders required to be obtained under antitrust laws or to avoid the entry or enactment of any injunction or other order or decree relating to any antitrust law that would delay, restrain, prevent, enjoin or otherwise prohibit consummation of the Transactions. Notwithstanding anything to the contrary in the Merger Agreement, Parent and its affiliates will not be required to, and, without the prior written consent of Parent, Forty Seven will not sell, license, divest or dispose of or hold separate (through the establishment of a trust or otherwise) or agree to any other structural, behavioral or conduct remedy, before or after the Offer Acceptance Time or the Effective Time, any entities, businesses, divisions, operations, products or product lines, assets, intellectual property rights or businesses or agree to any restriction on the conduct of such businesses which would materially and adversely affect the business of Parent and its subsidiaries, taken as a whole or would require the sale, license, divestiture, disposal or holding separate of or any other structural, behavioral or conduct remedy involving the product candidates. The foregoing actions will not require Parent or Forty Seven to take or agree to take any action unless the

38

effectiveness of such action is conditioned on the closing. Further, in no event will Parent, Purchaser, Forty Seven or any of their respective subsidiaries be obligated to litigate or participate in the litigation of any action, whether judicial or administrative, brought by any governmental body challenging or seeking to restrain, prohibit or place conditions on the consummation of the Transactions.

        Each of Forty Seven, Parent and Purchaser will (and will cause their respective affiliates, if applicable, to): (i) as promptly as reasonably practicable (but no later than ten (10) business days after the date of the Merger Agreement), make an appropriate filing of all Notification and Report forms as required by the HSR Act with respect to the Transactions and (ii) cooperate with each other in determining whether, and promptly preparing and making, any other filings, notifications or other consents are required to be made with, or obtained from, any other governmental bodies in connection with the Transactions.

        In addition Forty Seven, Parent and Purchaser have also agreed, until the Effective Time or the termination of the Merger Agreement pursuant to its terms, to: (i) promptly notify the other parties of the making or commencement of any request, inquiry, investigation, action or legal proceeding brought by a governmental body or brought by a third party before any governmental body, in each case, with respect to the Transactions under antitrust laws, (ii) keep the other parties reasonably informed as to the status of any such request, inquiry, investigation, action or legal proceeding, (iii) promptly inform the other parties of, and wherever practicable give the other party reasonable advance notice of, and the opportunity to participate in, any communication to or from the U.S. Federal Trade Commission (the "FTC"), the U.S. Department of Justice (the "DOJ") or any other governmental body in connection with any such request, inquiry, investigation, action or legal proceeding, (iv) promptly furnish to the other party, subject to an appropriate confidentiality agreement to limit disclosure to counsel and outside consultants, with copies of documents provided to or received from any governmental body in connection with any such request, inquiry, investigation, action or legal proceeding (except that documents, including "4(c) and 4(d) documents" as that term is used under the HSR Act, that contain valuation information can be redacted), (v) subject to an appropriate confidentiality agreement to limit disclosure to counsel and outside consultants, and to the extent reasonably practicable, consult and cooperate with the other parties and consider in good faith the views of the other parties in connection with any written analysis, appearance, presentation, memorandum, brief, argument, opinion or proposal made or submitted in connection with any such request, inquiry, investigation, action or legal proceeding, and (vi) except as may be prohibited by any governmental body or by any law, in connection with any such request, inquiry, investigation, action or legal proceeding in respect of the Transactions, give the other party reasonable prior notice and permit authorized Representatives of the other parties to be present at each meeting or conference, including by telephone, relating to such request, inquiry, investigation, action or legal proceeding and to have access to and be consulted in advance in connection with any argument, opinion or proposal made or submitted to any governmental body in connection with such request, inquiry, investigation, action or legal proceeding.

        During the period after the date of the Merger Agreement until the earlier of the Effective Time and the termination of the Merger Agreement pursuant to its terms, Forty Seven has agreed, to the extent permissible under applicable Legal Requirements and reasonably practicable and where doing so would not reasonably be expected to impair or adversely affect Forty Seven, any of its plans with respect to the product candidates or its ability to interact with any governmental body consistent with companies at a similar stage of development in the pharmaceutical industry (in each case as determined in good faith by Forty Seven), to (a) offer Parent the opportunity to consult with Forty Seven prior to any proposed material meeting or other material communication with the FDA, the European Medicines Agency (the "EMA"), the Centers for Medicare and Medicaid Services ("CMS") or any other specified governmental body relating to any product candidate or material governmental authorization, (b) promptly inform Parent of, and give Parent a reasonable opportunity to review in

39

advance, any material filing proposed to be made by or on behalf of Forty Seven and any material communication proposed to be submitted or given to the FDA, EMA, CMS or other specified governmental body by or on behalf of Forty Seven, in each case relating to any product candidate or material governmental authorization (provided that in clause (a) and (b), in no event will Forty Seven be required to delay any of its actions or such filings, correspondence and communication, respectively), (c) keep Parent reasonably informed of any material communication (written or oral) with or from the FDA, EMA, CMS or other specified governmental body or relating to any product candidate or governmental authorization, and (d) promptly inform Parent and provide Parent with a reasonable opportunity (but no more than two (2) business days to the extent practicable) to comment prior to making any material change to any study protocol, adding any new trial, making any material change to a manufacturing plan or process, making any material change to a development timeline or initiating or making any material change to, commercialization and reimbursement activities or material (including promotional and marketing activities and materials) relating to any product candidate. Forty Seven has agreed to promptly notify Parent of any significant data relating to any product candidate, including information related to any significant adverse events with respect to any product candidate, in each case which it discovers after the date of the Merger Agreement.

        The parties have agreed not to enter into any agreement, transaction, or any agreement to effect any transaction (including any merger or acquisition) that would reasonably be expected to make it materially more difficult, or to materially increase the time required, to (i) obtain the expiration or termination of the waiting period under the HSR Act, (ii) avoid the entry of, the commencement of litigation seeking the entry of, or to the effect the dissolution of, any injunction, temporary restraining order or other order that would materially delay or prevent the consummation of the transactions contemplated by the Merger Agreement or (iii) obtain all authorizations, consents, orders and approvals of governmental bodies necessary for the consummation of the transactions contemplated by the Merger Agreement.

        Employee Matters.    Parent has agreed that, for a period commencing at the Effective Time and ending on the one year anniversary of the Effective Time, it will provide to employees of Forty Seven who remain actively employed by Forty Seven or an affiliate during such period (the "Continuing Employees") (i) base salary or wage rate and annual cash bonus opportunities (excluding equity-based compensation opportunities) that are, in each case, no less than those provided by Forty Seven immediately prior to the Offer Acceptance Time, (ii) retirement and welfare benefits that are no less favorable in the aggregate than those provided by Forty Seven immediately prior to the Offer Acceptance Time and (iii) severance benefits no less favorable than those provided by Forty Seven immediately prior to the Offer Acceptance Time.

        Parent has also agreed that all Continuing Employees will be eligible to continue to participate in Forty Seven's health and welfare benefit plans (to the same extent such Continuing Employees were eligible to participate in Forty Seven's health and welfare benefit plans immediately prior to the Effective Time). Parent will also provide each Continuing Employee with service credit for all purposes under Parent and Forty Seven employee benefit plans for service prior to the Effective Time with Forty Seven to the same extent that such service was recognized under a corresponding Forty Seven employee benefit plan prior to the Effective Time. To the extent permitted under applicable law, Parent will and will cause Forty Seven to, with respect to any employee benefit plan maintained for the benefit of the Continuing Employees following the Effective Time, (a) waive any eligibility requirements, preexisting condition limitations or waiting period requirements to the same extent waived or satisfied under comparable plans of Forty Seven and (b) give effect, in determining any deductible, co-insurance and maximum out-of-pocket limitations, to amounts paid by such employees during the calendar year in which the Effective Time occurs under similar plans maintained by Forty Seven.

        To the extent requested in writing by Parent at least ten (10) days prior to the Offer Acceptance Time, Forty Seven will take all actions that may be necessary to terminate Forty Seven's 401(k) plan at

40

least one day prior to the Effective Time. If Forty Seven so terminates Forty Seven's 401(k), (i) prior to the Effective Time, Forty Seven and Parent will take any and all actions as may be required to permit each Continuing Employee to make rollover contributions of "eligible rollover distributions" in an amount equal to the full account balance distributed or distributable to each such employee from Forty Seven's 401(k) plan to the Parent 401(k) plan and (ii) each Continuing Employee will become a participant in Parent's 401(k) plan on the closing date (giving effect to the service-crediting provisions described above), such that no Continuing Employee will experience a gap in participation in a tax-qualified defined contribution plan.

        ESPP.    As soon as reasonably practicable after the date of the Merger Agreement, Forty Seven will take all necessary actions under its Employee Stock Purchase Plan (the "ESPP") to provide that (a) the "offering" (as defined in the ESPP) in effect as of the date of the Merger Agreement will be the final offering and (b) each individual participating in the final offering will not be permitted to increase his or her payroll contribution rate elected pursuant to the ESPP when the final offering commenced or make separate non-payroll contributions to the ESPP following the date of the Merger Agreement, except pursuant to applicable law. Prior to the Offer Acceptance Time, Forty Seven will take all action that may be necessary to, effective upon the Offer Acceptance Time, (i) cause the final offering to be terminated at least five (5) business days prior to when the Offer Acceptance Time occurs, (ii) make any pro rata adjustments that may be necessary to reflect the final offering, but otherwise treat the final offering as a fully effective and completed offering under the ESPP, and (iii) cause the exercise of each outstanding purchase right pursuant to the ESPP. On such exercise date, Forty Seven will apply the funds credited pursuant to the ESPP within each participant's payroll withholding account to the purchase of Shares in accordance with the terms of the ESPP and each Share will be an outstanding Share and entitled to the Merger Consideration. Forty Seven will adopt such resolutions as are necessary to terminate the ESPP effective as of immediately prior to, and conditional upon the occurrence of, the Offer Acceptance Time.

        Directors' and Officers' Indemnification and Insurance.    The Merger Agreement provides for indemnification, advancement of expenses, exculpation from liabilities and insurance rights in favor of the current and former directors and officers of Forty Seven, whom we refer to as "indemnitees," with respect to acts or omissions occurring at or prior to the Effective Time (whether asserted or claimed prior to, at or after the Effective Time). Specifically, for a period of six (6) years from and after the Effective Time (the "Indemnity Period"). Parent has agreed that all rights to indemnification, exculpation and advancement of expenses and exculpation from liabilities for acts or omissions occurring at or prior to the Effective Time (whether asserted or claimed prior to, at or after the Effective Time) now existing in favor of indemnitees as provided in governing documents, indemnification agreement or other similar agreements of Forty Seven with respect to all matters occurring prior to or at the Effective Time will continue in full force and effect in accordance with their respective terms and will not be amended, repealed or otherwise modified in any manner that would adversely effect the rights thereunder of any Indemnified Person (as defined below), and Parent will cause Forty Seven to perform its obligations thereunder.

        In addition, Parent has agreed that during the Indemnity Period Parent will cause the Surviving Corporation and its subsidiaries to, and the Surviving Corporation agrees that it will, indemnify and hold harmless each individual who is as of the date of the Merger Agreement, or who becomes prior to the Effective Time, a director or officer of Forty Seven or who is as of the date of the Merger Agreement, or who thereafter commences prior to the Effective Time, serving at the request of Forty Seven as a director or officer of another person (the "Indemnified Persons"), against all claims, losses, liabilities, damages, judgments, inquiries, fines and reasonable fees, costs and expenses, including attorneys' fees and disbursements, incurred in connection with any claim, action, suit or proceeding, whether civil, criminal, administrative or investigative (including with respect to matters existing or occurring prior to the Effective Time, including the Merger Agreement and the transactions and

41

actions contemplated thereby), arising out of or pertaining to the fact that the Indemnified Person is or was a director or officer of Forty Seven or is or was serving at the request of Forty Seven as a director or officer of another person, whether asserted or claimed prior to, at or after the Effective Time, to the fullest extent permitted under applicable legal requirements. The Merger Agreement provides that each Indemnified Person will be entitled to advancement of expenses incurred in the defense of any such claim, action, suit or proceeding from Parent, the Surviving Corporation or its subsidiaries, as applicable, in accordance with the organizational documents and any indemnification or other similar agreements of Forty Seven as in effect on the date of the Merger Agreement. If and only to the extent required by the DGCL or Forty Seven's organizational documents or any indemnification or other similar agreements, as applicable, any Indemnified Person to whom expenses are advanced may be required to provide an undertaking to repay such advances if it is ultimately determined by final adjudication that such Indemnified Person is not entitled to indemnification. Further, Parent, the Surviving Corporation and its subsidiaries, as applicable, will reasonably cooperate in the defense of any such matter.

        For the Indemnity Period, Parent and the Surviving Corporation have agreed to either cause to be maintained in effect the current policies of directors' and officers' liability insurance maintained by Forty Seven or provide substitute policies for Forty Seven (and its current and former directors and officers who are currently covered by Forty Seven's existing policies), in either case of not less than the existing coverage and having other terms not less favorable to the insured persons than such insurance coverage currently maintained by Forty Seven with respect to claims arising from facts or events that occurred at or prior to the Effective Time (with insurance carriers having at least an "A" rating by A.M. Best with respect to directors' and officers' liability insurance); provided that neither Parent nor the Surviving Corporation will be required to pay with respect to such insurance policies an annual premium greater than 300% of the aggregate annual premium most recently paid by Forty Seven for such insurance (the "Maximum Amount"). In lieu of the foregoing, prior to the closing date, Forty Seven may purchase a "tail" directors' and officers' liability insurance policy for Forty Seven (and its current and former directors and officers who are currently covered by Forty Seven's existing policies) to provide coverage in an amount not less than the existing coverage and to have other terms not less favorable to the insured persons than the insurance coverage currently maintained by Forty Seven with respect to claims arising from facts or events that occurred at or before the Effective Time, provided that the cost of any such tail policy will not exceed the Maximum Amount.

        Reasonable Best Efforts.    Each of Forty Seven and Parent has agreed to use its respective reasonable best efforts to take, or cause to be taken, all actions necessary to consummate the Offer and the Merger and make effective the other Transactions. In particular, each party has agreed to use commercially reasonable efforts to (i) make all filings (if any) and give all notices (if any) required to be made and given pursuant to any material contract in connection with the Offer and the Merger and the other Transactions to the extent requested in writing by Parent, (ii) seek each consent (if any) required to be obtained pursuant to any material contract in connection with the Transactions to the extent requested in writing by Parent, provided that obtaining any such consent or approval will not, in and of itself, be a condition to the Offer or the Merger, and (iii) seek to lift any restraint, injunction or other legal bar to the Offer or the Merger brought by any third person against such party. Neither Parent, Forty Seven nor any of their respective subsidiaries will be required to pay any consent or other similar fee, payment or consideration, make any other concession or provide any additional security (including a guaranty), to obtain any third party consents.

        Security Holder Litigation.    In the event that any litigation related to the Merger Agreement, the Offer, the Merger or the other Transactions is brought by any stockholder or other holder of any Forty Seven securities (whether directly or on behalf of Forty Seven or otherwise) against Forty Seven and/or its directors or officers, Forty Seven is required to promptly notify Parent of such litigation and to keep Parent reasonably informed with respect to the status thereof. Forty Seven has agreed to give Parent

42

(a) the opportunity to participate in the defense of any such litigation, (b) the right to review and comment on all material filings or responses to be made by Forty Seven in connection with such litigation (and Forty Seven will give due consideration to Parent's comments and other advice with respect to such litigation) and (c) the right to consult on any settlement with respect to such litigation, and no such settlement will be agreed to without Parent's prior written consent (such consent not to be unreasonably withheld), provided that in no event will Parent be required to consent (such consent not to be unreasonably withheld, conditioned or delayed) to any settlement that does not provide for unconditional release of Parent, its affiliates, representatives and other persons entitled to indemnification by Parent or Forty Seven from any liability in connection with the litigation. Forty Seven will otherwise control the defense and/or settlement described above and the disclosure of information in connection with such defense or settlement will be subject to the access and notice provisions described above, including regarding attorney-client privilege or other applicable legal privilege.

        Takeover Laws.    If any "moratorium," "control share acquisition," "fair price," "supermajority," "affiliate transactions," or "business combination statute or regulation" or other similar state anti-takeover laws and regulations (including Section 203 of the DGCL) (each, a "Takeover Law") may become, or may purport to be, applicable to the Transactions, Parent and Forty Seven have agreed to use their respective reasonable best efforts to grant such approvals and take such actions as are necessary so that the Transactions may be consummated as promptly as practicable on the terms and conditions contemplated by the Merger Agreement and otherwise act to lawfully eliminate the effect of any Takeover Law on any of the Transactions.

        Section 16 Matters.    Forty Seven and the Forty Seven Board (or a duly formed committee thereof consisting of non-employee directors (as such term is defined for the purposes of Rule 16b-3 promulgated under the Exchange Act)) will, to the extent necessary, take appropriate action, prior to or as of the Offer Acceptance Time, to approve, for the purposes of Section 16(b) of the Exchange Act, the disposition and cancellation (or deemed disposition and cancellation) of Shares and Company Options in the Merger by applicable individuals and to cause such dispositions and/or cancellations to be exempt under Rule 16b-3 promulgated under the Exchange Act.

        Stock Exchange Delisting and Deregistration.    Prior to the closing date, Forty Seven has agreed to cooperate with Parent and to use its reasonable best efforts to take, or cause to be taken, all actions, and do or cause to be done all things, reasonably necessary, proper or advisable under applicable laws and rules and policies of NASDAQ to enable delisting by Forty Seven of the Shares from NASDAQ and the deregistration of the Shares under the Exchange Act as promptly as practicable after the Effective Time.

        No Solicitation.    Except as described below, until the earlier of the Effective Time or the valid termination of the Merger Agreement pursuant to its terms, Forty Seven has agreed not to, and to cause its directors and officers not to, and to direct and use its reasonable best efforts to cause its other Representatives not to, directly or indirectly:

43

        Forty Seven agreed to, as promptly as reasonably practicable (and in any event within two (2) business days) following the date of the Merger Agreement, discontinue electronic or physical data room access granted and request the prompt return or destruction (to the extent provided for by the applicable confidentiality agreement) of all information or documents previously furnished to any person (other than Parent, its affiliates and their respective Representatives) that has made or has indicated an intention to make an Acquisition Proposal and all material incorporating such information created by any such person.

        Notwithstanding the above limitations, if Forty Seven or any of its Representatives receives after the date of the Merger Agreement and prior to the Offer Acceptance Time a bona fide written Acquisition Proposal from any person or group of persons, which Acquisition Proposal was made on or after the date of the Merger Agreement, that did not result from a material breach of the non-solicitation provisions of the Merger Agreement and the Forty Seven Board determines in good faith, after consultation with its financial advisor and outside legal counsel, that such an Acquisition Proposal constitutes or would reasonably be expected to result in a Superior Offer (as defined below) and that the failure to take such action (as described below) would be inconsistent with its fiduciary duties under applicable legal requirements, Forty Seven and its Representatives may take the following actions:

        In the case of each of clauses (x) and (y) above, at or prior to the first time Forty Seven furnishes such information or participates in any such discussions or negotiations, Forty Seven must provide written notice to Parent of the required determination in good faith of the Forty Seven Board as described above. Under the Merger Agreement "Acceptable Confidentiality Agreement" means any customary confidentiality agreement that is (a) in effect as of the execution and delivery of the Merger Agreement or (b) executed, delivered and effective after the execution and delivery of the Merger Agreement that (i) contains provisions that are not less favorable in the aggregate to Forty Seven than those contained in the Mutual Confidential Disclosure Agreement, effective as of January 7, 2020, between Forty Seven and Parent (the "Confidentiality Agreement"), provided that such agreement

44

need not contain any "standstill" or similar provisions or otherwise prohibit the making of any Acquisition Proposal, and (ii) does not prohibit Forty Seven from providing any of the information described above to Parent.

        Forty Seven is required to notify Parent promptly (but in any event within thirty-six (36) hours) of the receipt by Forty Seven or any of its Representatives of any inquiry, proposal or offer with respect to, or that would reasonably be expected to lead to, an Acquisition Proposal. Forty Seven is further required to (i) provide Parent a copy of any written Acquisition Proposal and a summary of any material unwritten terms and conditions thereof, (ii) identify the person making such inquiry, proposal or offer, and (iii) keep Parent reasonably informed of any material developments, discussions or negotiations regarding any Acquisition Proposal on a prompt basis (and in any event within thirty-six (36) hours of such material development, discussion or negotiation).

        "Acquisition Proposal" means any proposal or offer from any person or group, including any amendment or modification to any existing proposal or offer, relating to, in a single transaction or series of related transactions, any (i) acquisition or license of assets of Forty Seven equal to 20% or more of Forty Seven's consolidated assets; (ii) acquisition or exclusive license of the product candidates, (iii) issuance or acquisition of 20% or more of Forty Seven's outstanding Shares; (iv) recapitalization, tender offer or exchange offer that if consummated would result in any person or group beneficially owning 20% or more of Forty Seven's outstanding Shares; or (v) merger, consolidation, amalgamation, share exchange, business combination, recapitalization, liquidation, dissolution or similar transaction involving Forty Seven that if consummated would result in any person or group beneficially owning 20% or more of Forty Seven's outstanding Shares (in the case of each of foregoing paragraphs (i) through (iv), other than the Transactions.

        "Superior Offer" means a bona fide written Acquisition Proposal (except that references to "20%" in the definition of Acquisition Proposal above will be deemed to be "50%"), not solicited in violation of the Merger Agreement, that the Forty Seven Board determines, in its good faith judgment, after consultation with outside legal counsel and its financial advisor, is reasonably likely to be consummated in accordance with its terms, taking into account all legal, regulatory and financing aspects of the proposal and the person making the proposal and other aspects of the Acquisition Proposal that the Forty Seven Board deems relevant, and if consummated, would result in a transaction more favorable to Forty Seven's stockholders (solely in their capacity as such) from a financial point of view than the Transactions (including after giving effect to any revisions to the terms of the Merger Agreement proposed by Parent or any other proposal of Parent so that such Acquisition Proposal would cease to constitute a Superior Offer).

        Nothing in the Merger Agreement will prohibit Forty Seven from disclosing to Forty Seven's stockholders any "stop, look and listen" communication pursuant to Rule 14d-9(f) promulgated under the Exchange Act or from taking and disclosing such other position or disclosure as required under Rule 14e-2(a), Rule 14d-9 or Item 1012(a) of Regulation M-A promulgated under the Exchange Act, or from taking any action necessary to comply with applicable legal requirements, provided that the Forty Seven Board will not effect a Company Adverse Change Recommendation (as defined below) except as set forth below.

        Forty Seven has agreed that in the event any Representative of Forty Seven acting on behalf of Forty Seven takes any action that, if taken by Forty Seven, would constitute a breach of the provisions summarized under this "—No Solicitation" heading, Forty Seven will be deemed to be in breach of such provisions.

        Recommendation Change.    As described above, and subject to the provisions described below, the Forty Seven Board has determined to recommend that the stockholders of Forty Seven accept the Offer and tender their Shares to Purchaser in the Offer. The foregoing recommendation is referred to herein as the "Company Board Recommendation." The Forty Seven Board also agreed to include the Company Board Recommendation with respect to the Offer in the Schedule 14D-9 and has permitted Parent to refer to such recommendation in this Offer to Purchase and documents related to the Offer.

45

        Except as described below, prior to the Effective Time or the termination of the Merger Agreement pursuant to its terms, neither the Forty Seven Board nor any committee thereof may:

        The Merger Agreement further provides that the Forty Seven Board will not approve, recommend or declare advisable, or propose to approve, recommend or declare advisable, or cause or allow Forty Seven to execute or enter into any contract, letter of intent, memorandum of understanding, agreement in principle or term sheet with respect to, or that is intended to or would reasonably be expected to lead to, any Acquisition Proposal, or requiring, or reasonably expected to cause, Forty Seven to abandon, terminate, delay or fail to consummate, or that would otherwise materially impede, interfere with or be inconsistent with, the Transactions (other than an Acceptable Confidentiality Agreement).

        Notwithstanding anything to the contrary in the Merger Agreement, at any time prior to the Offer Acceptance Time, the Forty Seven Board may, subject to compliance with the other provisions summarized under this "—Recommendation Change" heading, make a Company Adverse Change Recommendation in response to a Superior Offer or (provided Forty Seven is not in breach of the non-solicitation provisions in any material respect and in a manner that led to such Acquisition Proposal) terminate the Merger Agreement in order to enter into an agreement with respect to such Superior Offer. However, such action may only be taken if:

46

        The foregoing paragraphs (i) through (iv) also apply to any change to any of the financial terms (including the form, amount and timing of payment of consideration) or other material amendment to any Acquisition Proposal and require a new Determination Notice, except that the references to three (3) business days will be deemed to be two (2) business days.

        Additionally, at any time prior to the Offer Acceptance Time, the Forty Seven Board may, subject to compliance with the other provisions summarized under this "—Recommendation Change" heading, effect a Company Adverse Change Recommendation in response to an Intervening Event (as defined below). However, such action may only be taken if:

47

The foregoing paragraphs (ii) through (iv) also apply to any material change to the facts and circumstances specified by Forty Seven pursuant to clause (iv)(A) above and require a new Determination Notice, except that the references to three (3) business days will be deemed to be two (2) business days.

        Termination.    The Merger Agreement may be terminated prior to the Offer Acceptance as follows:

48

        Effect of Termination.    If the Merger Agreement is terminated pursuant to its terms, the Merger Agreement will be of no further force or effect and there will be no liability on the part of Parent, Purchaser or Forty Seven (or any of their respective former, current or future officers, directors, partners, stockholders, managers, members or affiliates) following any such termination, except that (i) certain specified provisions of the Merger Agreement will survive, including those described in "—Forty Seven Termination Fee" below, (ii) the Confidentiality Agreement will survive the termination of the Merger Agreement and remain in full force and effect in accordance with its terms and

49

(iii) except as set forth in the Merger Agreement, termination will not relieve any party from liability for fraud or willful and material breach of the Merger Agreement prior to such termination.

        Forty Seven Termination Fee.    Forty Seven has agreed to pay Parent a termination fee of $160 million in cash (the "Termination Fee") if:

        In the event Parent receives the Termination Fee, such receipt will be deemed to be liquidated damages for, and the sole and exclusive monetary remedy available to Parent and Purchaser in connection with, any and all losses or damages suffered or incurred by Parent, Purchaser, any of their respective affiliates or any other person in connection with the Merger Agreement (collectively, "Parent Related Parties") (and the termination thereof), the Transactions (and the abandonment thereof) or any matter forming the basis for such termination, and none of Parent, Purchaser or any of their respective affiliates will be entitled to bring or maintain any claim, action or proceeding against Forty Seven or any of its affiliates arising out of or in connection with the Merger Agreement, any of the Transactions or any matters forming the basis for such termination. In no event will Forty Seven be required to pay the Termination Fee on more than one occasion.

        Parent's right to receive the payment from Forty Seven of the Termination Fee will be the sole and exclusive remedy of the Parent Related Parties against Forty Seven and any of its former, current or future officers, directors, partners, stockholders, optionholders, managers, members or affiliates (collectively, "Company Related Parties") for any loss or damages suffered as a result of the failure of the Offer or the Merger to be consummated or for a breach or failure to perform under the Merger Agreement or otherwise, and upon payment of such amount(s), none of the Company Related Parties will have any further liability or obligation relating to or arising out of the Merger Agreement or the Transactions.

        Specific Performance.    The parties have agreed that irreparable damage would occur in the event that any of the provisions of the Merger Agreement were not performed in accordance with their specific terms or were otherwise breached. The parties further agreed that the parties will be entitled to an injunction or injunctions, specific performance or other equitable relief to prevent breaches of the Merger Agreement and to enforce specifically the terms and provisions of the Merger Agreement, without proof of damages or otherwise, in addition to any other remedy to which they are entitled under the Merger Agreement. The right to specific performance includes the right of Forty Seven, on behalf of itself and any third party beneficiaries to the Merger Agreement, to cause Parent and

50

Purchaser to cause the Offer, the Merger and the other Transactions to be consummated on the terms and conditions set forth in the Merger Agreement.

        Expenses.    Except as otherwise provided in the Merger Agreement, all fees and expenses incurred by the parties in connection with the Merger Agreement and the Transactions will be paid by the party incurring such expenses, whether or not the Offer and Merger are consummated.

        Offer Conditions.    The Offer Conditions are described in Section 13—"Conditions of the Offer."

        Prior to signing the Merger Agreement, Parent and Forty Seven entered into the Confidentiality Agreement, pursuant to which each party agreed, subject to certain exceptions, to keep confidential nonpublic information about the other party in connection with the consideration of a possible business transaction involving Parent and Forty Seven. Parent's and Forty Seven's obligations with respect to confidential information under the Confidentiality Agreement survive termination or expiration of the Confidentiality Agreement, and will expire seven (7) years after the date of the Confidentiality Agreement. The Confidentiality Agreement does not include (i) an employee non-solicitation provision or (ii) a standstill provision.

        This summary does not purport to be complete and is qualified in its entirety by reference to the Confidentiality Agreement, which is filed as Exhibit (d)(2) to the Schedule TO and is incorporated by reference herein.

12.   Source and Amount of Funds.

        The Offer is not conditioned upon Parent's or Purchaser's ability to finance the purchase of Shares pursuant to the Offer. Parent and Purchaser estimate that the total amount of funds required to consummate the Merger (including payments for options and other payments referred to in the Merger Agreement) pursuant to the Merger Agreement and to purchase all of the Shares pursuant to the Offer and the Merger Agreement will be approximately $4.9 billion at or prior to the Closing. The funds to pay for all Shares accepted for payment in the Offer and the consideration in connection with the Merger are expected to come from Parent's available cash and cash equivalents on hand.

        We do not believe our financial condition is relevant to your decision whether to tender your Shares and accept the Offer because (i) the Offer is being made for all outstanding Shares solely for cash, (ii) the Offer is not subject to any financing condition, (iii) if we consummate the Offer, we will acquire all remaining Shares for the same price in the Merger, and (iv) Parent and/or one or more of its affiliates has, and will arrange for us to have, sufficient funds to purchase all Shares validly tendered in the Offer, and not properly withdrawn, to acquire the remaining outstanding Shares in the Merger on the terms set forth in this Offer to Purchase.

13.   Conditions of the Offer.

        The obligation of Purchaser to accept for payment and pay for Shares validly tendered and not validly withdrawn pursuant to the Offer is subject to the satisfaction of the conditions set forth in clauses (a) through (k) below. Notwithstanding any other provisions of the Offer or the Merger Agreement to the contrary and subject to any applicable rules and regulations of the SEC including Rule 14e-1(c) of the Exchange Act, Purchaser is not required to accept for payment or pay for, and may delay the acceptance for payment of, or the payment for, any tendered Shares, and, to the extent permitted by the Merger Agreement, may terminate the Offer (i) upon termination of the Merger Agreement; and (ii) at any scheduled Expiration Date (subject to any extensions of the Offer), if: (A) the Minimum Tender Condition (described in clause (a) below), the Termination Condition (described in clause (k) below), the HSR Condition (described in clause (h) below), and the

51

Governmental Impediment Condition (described in clause (j) below) shall not be satisfied by one minute after 11:59 p.m., Eastern Time on the Expiration Date; or (B) any of the additional conditions described below has not been satisfied or waived in writing by Parent:

52

        The foregoing conditions are for the sole benefit of Parent and Purchaser, may be asserted by Parent or Purchaser regardless of the circumstances giving rise to any such conditions (including any action or inaction by Parent or Purchaser), and (except for the Minimum Tender Condition) may be waived by Parent and Purchaser, in whole or in part, at any time and from time to time, in their sole and absolute discretion. The failure by Parent or Purchaser at any time to exercise any of the foregoing rights will not be deemed a waiver of any such right and each such right will be deemed an ongoing right which may be asserted at any time and from time to time prior to the expiration of the Offer (except for conditions relating to government regulatory approvals).

14.   Dividends and Distributions.

        The Merger Agreement provides that Forty Seven will not, between the date of the Merger Agreement and the Effective Time, establish a record date for, declare, set aside or pay any dividends on or make other distribution in respect of any shares of its capital stock (including the Shares). See Section 11—"Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements—Summary of the Merger Agreement—Conduct of Business Pending the Merger."

15.   Certain Legal Matters; Regulatory Approvals.

        General.    Except as otherwise set forth in this Offer to Purchase, based on Parent's and Purchaser's review of publicly available filings by Forty Seven with the SEC and other information regarding Forty Seven, Parent and Purchaser are not aware of any licenses or other regulatory permits which appear to be material to the business of Forty Seven and which might be adversely affected by the acquisition of Shares by Purchaser or Parent pursuant to the Offer or of any approval or other action by any governmental, administrative or regulatory agency or authority which would be required for the acquisition or ownership of Shares by Purchaser or Parent pursuant to the Offer. In addition, except as set forth below, Parent and Purchaser are not aware of any filings, approvals or other actions by or with any governmental body or administrative or regulatory agency that would be required for Parent's and Purchaser's acquisition or ownership of the Shares. Should any such approval or other action be required, Parent and Purchaser currently expect that such approval or action, except as described below under "State Takeover Laws," would be sought or taken. There can be no assurance that any such approval or action, if needed, would be obtained or, if obtained, that it will be obtained without substantial conditions; and there can be no assurance that, in the event that such approvals were not obtained or such other actions were not taken, adverse consequences might not result to Forty Seven's or Parent's business or that certain parts of Forty Seven's or Parent's business might not

53

have to be disposed of or held separate. In such an event, we may not be required to purchase any Shares in the Offer. See Section 13—"Conditions of the Offer."

        Antitrust.    Under the HSR Act, and the rules and regulations promulgated thereunder by the FTC, certain transactions may not be consummated until certain information and documentary materials have been furnished for review to the FTC and the Antitrust Division of the DOJ (the "Antitrust Division") and certain waiting period requirements have been satisfied. These requirements apply to Parent by virtue of Purchaser's acquisition of the Shares in the Offer (and the Merger).

        Under the HSR Act, the purchase of Shares in the Offer may not be completed until the expiration of a fifteen (15)-calendar-day waiting period following the filing of certain required information and documentary material concerning the Offer (and the Merger) with the FTC and the Antitrust Division, unless the waiting period is earlier terminated by the FTC and the Antitrust Division. The parties agreed in the Merger Agreement to file such Premerger Notification and Report Forms under the HSR Act with the FTC and the Antitrust Division in connection with the purchase of Shares in the Offer and the Merger as promptly as reasonably practicable, but no later than ten (10) business days from the date of the Merger Agreement. Under the HSR Act, the required waiting period will expire at 11:59 pm, Eastern Time on the 15th calendar day after the filing by Parent, unless earlier terminated by the FTC and the Antitrust Division or Parent receives a request for additional information or documentary material ("Second Request") from either the FTC or the Antitrust Division prior to that time. If a Second Request issues, the waiting period with respect to the Offer (and the Merger) would be extended for an additional period of ten calendar days following the date of Parent's substantial compliance with that request. If either the 15-day or ten-day waiting period expires on a Saturday, Sunday or federal holiday, then the period is extended until 11:59 p.m. of the next day that is not a Saturday, Sunday or federal holiday. Only one extension of the waiting period pursuant to a Second Request is authorized by the HSR Act rules. After that time, the waiting period could be extended only by court order or with Parent's consent. The FTC or the Antitrust Division may terminate the additional ten-day waiting period before its expiration. Complying with a Second Request can take a significant period of time. Although Forty Seven is also required to file certain information and documentary material with the FTC and the Antitrust Division in connection with the Offer, neither Forty Seven's failure to make its filing nor failure to comply with its own Second Request in a timely manner will extend the waiting period with respect to the purchase of Shares in the Offer (and the Merger).

        The FTC and the Antitrust Division frequently scrutinize the legality under the U.S. antitrust laws of transactions, such as Purchaser's acquisition of Shares in the Offer (and the Merger). At any time before or after Purchaser's purchase of Shares in the Offer (and the Merger), the FTC or the Antitrust Division could take any action under the antitrust laws that it either considers necessary or desirable in the public interest, including seeking to enjoin the purchase of Shares in the Offer (and the Merger), the divestiture of Shares purchased in the Offer and Merger or the divestiture of substantial assets of Parent, Forty Seven or any of their respective subsidiaries or affiliates. Private parties, as well as state attorneys general, also may bring legal actions under the antitrust laws under certain circumstances. See Section 13—"Conditions of the Offer."

        Parent and Forty Seven also conduct business outside of the United States. However, based on a review of the information currently available relating to the countries and businesses in which Parent and Forty Seven are engaged, Parent and Purchaser believe that no mandatory antitrust premerger notification filing is required outside the United States and approval of any non-U.S. antitrust authority is not a condition to the consummation of the Offer or the Merger.

        Based upon an examination of publicly available and other information relating to the businesses in which Forty Seven is engaged, Parent and Purchaser believe that the acquisition of Shares in the Offer (and the Merger) should not violate applicable antitrust laws. Nevertheless, Parent and Purchaser

54

cannot be certain that a challenge to the Offer (and the Merger) on antitrust grounds will not be made, or, if such challenge is made, what the result will be. See Section 13—"Conditions of the Offer."

        Stockholder Approval Not Required.    Forty Seven has represented in the Merger Agreement that execution, delivery and performance of the Merger Agreement by Forty Seven and the consummation by Forty Seven of the Offer and the Merger have been duly and validly authorized by all necessary corporate action on the part of Forty Seven, and no other corporate proceedings on the part of Forty Seven are necessary to authorize the Merger Agreement or to consummate the Offer and the Merger. Section 251(h) of the DGCL provides that stockholder approval of a merger is not required if certain requirements are met, including that (i) the acquiring company consummates an offer for all of the outstanding stock of the company to be acquired that, absent Section 251(h) of the DGCL, would be entitled to vote on the merger, and (ii) following the consummation of such tender offer, the acquiring company owns at least such percentage of the stock of the company to be acquired that, absent Section 251(h) of the DGCL, would be required to adopt the merger agreement. If the Minimum Tender Condition is satisfied and we accept Shares for payment pursuant to the Offer, we will hold a sufficient number of Shares to ensure that Forty Seven will not be required to submit the adoption of the Merger Agreement to a vote of its stockholders. Following the consummation of the Offer and subject to the satisfaction of the remaining conditions set forth in the Merger Agreement, Purchaser, Parent and Forty Seven will take all necessary and appropriate action to effect the Merger as promptly as practicable without a meeting of stockholders of Forty Seven in accordance with Section 251(h) the DGCL. See Section 11—"Purpose of the Offer and Plans for Forty Seven; Summary of the Merger Agreement and Certain Other Agreements."

        State Takeover Laws.    A number of states (including Delaware, where Forty Seven is incorporated) have adopted takeover laws and regulations which purport, to varying degrees, to be applicable to attempts to acquire securities of corporations which are incorporated in such states or which have substantial assets, stockholders, principal executive offices or principal places of business therein.

        As a Delaware corporation, Forty Seven has not opted out of Section 203 of the DGCL. In general, Section 203 of the DGCL would prevent an "interested stockholder" (generally defined in Section 203 of the DGCL as a person beneficially owning 15% or more of a corporation's voting stock) from engaging in a "business combination" (as defined in Section 203 of the DGCL) with a Delaware corporation for three years following the time such person became an interested stockholder unless: (i) before such person became an interested stockholder, the board of directors of the corporation approved the transaction in which the interested stockholder became an interested stockholder or approved the business combination; (ii) upon consummation of the transaction which resulted in the interested stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced (excluding for purposes of determining the number of shares of outstanding stock held by directors who are also officers and by employee stock plans that do not allow plan participants to determine confidentially whether to tender shares); or (iii) following the transaction in which such person became an interested stockholder, the business combination is (a) approved by the board of directors of the corporation and (b) authorized at a meeting of stockholders by the affirmative vote of the holders of at least 662/3% of the outstanding voting stock of the corporation not owned by the interested stockholder.

        Forty Seven has represented to us in the Merger Agreement that it has taken all actions necessary or appropriate to exempt the execution, delivery, and performance of the Merger Agreement and the Offer, the Merger, and the other transactions contemplated by the Merger Agreement from Section 203 of the DGCL and any other "moratorium," "control share acquisition," "fair price," "super majority," "affiliate transactions," or "business combination" or other similar state anti-takeover laws and regulations. Purchaser has not attempted to comply with any other state takeover statutes in connection with the Offer or the Merger. Purchaser reserves the right to challenge the validity or

55

applicability of any state law allegedly applicable to the Offer, Merger, the Merger Agreement or the transactions contemplated thereby, and nothing in this Offer to Purchase or any action taken in connection herewith is intended as a waiver of that right. In the event that it is asserted that one or more takeover statutes apply to the Offer or the Merger, and it is not determined by an appropriate court that such statute or statutes do not apply or are invalid as applied to the Offer, Merger, or the Merger Agreement, as applicable, Purchaser may be required to file certain documents with, or receive approvals from, the relevant state authorities, and Purchaser might be unable to accept for payment or purchase Shares tendered pursuant to the Offer or be delayed in continuing or consummating the Offer. In such case, Purchaser may not be obligated to accept for purchase, or pay for, any Shares tendered. See Section 13—"Conditions of the Offer."

        Appraisal Rights.    No appraisal rights are available to the holders of Shares in connection with the Offer. However, if the Offer is successful and the Merger is consummated, stockholders of Forty Seven who (i) did not tender their Shares in the Offer; (ii) otherwise comply with the applicable requirements and procedures of Section 262 of the DGCL; and (iii) do not thereafter withdraw their demand for appraisal of such Shares or otherwise lose their appraisal rights, in each case in accordance with the DGCL, will be entitled to demand appraisal of their Shares and receive in lieu of the consideration payable in the Offer a cash payment equal to the "fair value" of their Shares, as determined by the Delaware Court of Chancery, in accordance with Section 262 of the DGCL. If you choose to exercise your appraisal rights in connection with the Merger and you properly demand and perfect such rights in accordance with Section 262 of the DGCL, you may be entitled to payment for your Shares based on a judicial determination of the fair value of your Shares.

        Any such judicial determination of the fair value of the Shares could be based upon considerations other than or in addition to the price paid in the Offer and the market value of the Shares. Stockholders should recognize that the value so determined could be higher or lower than the price per Share paid pursuant to the Offer or the per Share price to be paid in the Merger. Moreover, Forty Seven may argue in an appraisal proceeding that, for purposes of such a proceeding, the fair value of the Shares is less than the price paid in the Offer and the Merger.

        Under Section 262 of the DGCL, where a merger is approved under Section 251(h), either a constituent corporation before the effective date of the merger, or the surviving corporation within ten days thereafter, shall notify each of the holders of any class or series of stock of such constituent corporation who are entitled to appraisal rights of the approval of the merger or consolidation and that appraisal rights are available for any or all shares of such class or series of stock of such constituent corporation, and shall include in such notice a copy of Section 262 of the DGCL. The Schedule 14D-9 constitutes the formal notice of appraisal rights under Section 262 of the DGCL.

        As described more fully in the Schedule 14D-9, if a stockholder elects to exercise appraisal rights under Section 262 of the DGCL, the stockholder must (i) prior to the later of the consummation of the Offer and 20 days after the mailing of the Schedule 14D-9, deliver to Forty Seven a written demand for appraisal of his, her or its Shares, which demand must reasonably inform Forty Seven of the identity of the stockholder and that the stockholder is demanding appraisal; (ii) not tender his, her or its Shares in the Offer; (iii) continuously hold of record the Shares from the date on which the written demand for appraisal is made through the Effective Time; and (iv) comply with the procedures of Section 262 of the DGCL for perfecting appraisal rights thereafter.

        The foregoing summary of the rights of dissenting stockholders under the DGCL does not purport to be a statement of the procedures to be followed by stockholders desiring to exercise any appraisal rights under Delaware law. The preservation and exercise of appraisal rights require strict and timely adherence to the applicable provisions of Delaware law which will be set forth in their entirety in the notice of merger. The foregoing discussion is not a complete statement of law pertaining to appraisal rights under Delaware law and is qualified in its entirety by reference to Delaware law, including

56

without limitation, Section 262 of the DGCL, a copy of which is included as Annex B to the Schedule 14D-9.

        The information provided above is for informational purposes only with respect to your alternatives if the Merger is consummated. Any stockholder who desires to exercise his, her or its appraisal rights should review carefully Section 262 of the DGCL and is urged to consult his, her or its legal advisor before electing or attempting to exercise such rights. The foregoing summary does not constitute any legal or other advice nor does it constitute a recommendation that Forty Seven stockholders exercise appraisal rights under Section 262 of the DGCL.

        If you tender your Shares into the Offer, you will not be entitled to exercise appraisal rights with respect to your Shares but, instead, subject to the conditions to the Offer, you will receive the Offer Price for your Shares.

        "Going Private" Transactions.    Rule 13e-3 under the Exchange Act is applicable to certain "going private" transactions and may under certain circumstances be applicable to the Merger. However, Rule 13e-3 will be inapplicable if (i) the Shares are deregistered under the Exchange Act prior to the Merger or another business combination or (ii) the Merger or other business combination is consummated within one year after the purchase of the Shares pursuant to the Offer and the amount paid per Share in the Merger or other business combination is at least equal to the amount paid per Share in the Offer. Neither Parent nor Purchaser believes that Rule 13e-3 will be applicable to the Merger.

        Legal Proceedings Relating to the Tender Offer.    None.

16.   Fees and Expenses.

        Parent has retained the Depositary and the Information Agent in connection with the Offer. The Depositary and the Information Agent will receive customary compensation, reimbursement for reasonable out-of-pocket expenses and indemnification against certain liabilities in connection with the Offer, including certain liabilities under the federal securities laws.

        As part of the services included in such retention, the Information Agent may contact holders of Shares by personal interview, mail, electronic mail, telephone, telex, telegraph and other methods of electronic communication and may request brokers, dealers, commercial banks, trust companies and other nominees to forward the Offer materials to beneficial holders of Shares.

        Except as set forth above, neither Parent nor Purchaser will pay any fees or commissions to any broker or dealer or other person for soliciting tenders of Shares pursuant to the Offer. Brokers, dealers, commercial banks and trust companies will upon request be reimbursed by us for customary mailing and handling expenses incurred by them in forwarding the offering material to their customers.

17.   Miscellaneous.

        The Offer is being made to all holders of the Shares. We are not aware of any jurisdiction in which the making of the Offer or the acceptance thereof would be prohibited by securities, "blue sky" or other valid laws of such jurisdiction. If we become aware of any U.S. state in which the making of the Offer or the acceptance of Shares pursuant thereto would not be in compliance with an administrative or judicial action taken pursuant to a U.S. state statute, we will make a good faith effort to comply with any such law. If, after such good faith effort, we cannot comply with any such law, the Offer will not be made to (nor will tenders be accepted from or on behalf of) the holders of Shares in such state. In any jurisdictions where applicable laws require the Offer to be made by a licensed broker or dealer, the Offer shall be deemed to be made on behalf of Purchaser by one or more registered brokers or dealers licensed under the laws of such jurisdiction to be designated by Purchaser.

57

        Parent and Purchaser have filed with the SEC the Schedule TO (including exhibits) in accordance with the Exchange Act, furnishing certain additional information with respect to the Offer, and may file amendments thereto. The Schedule TO and any amendments thereto, including exhibits, may be examined and copies may be obtained from the SEC in the manner set forth in Section 8—"Certain Information Concerning Forty Seven" under "Available Information."

        The Offer does not constitute a solicitation of proxies for any meeting of Forty Seven's stockholders. Any solicitation of proxies which Purchaser or any of its affiliates might seek would be made only pursuant to separate proxy materials complying with the requirements of Section 14(a) of the Exchange Act.

        No person has been authorized to give any information or make any representation on behalf of Parent or Purchaser not contained in this Offer to Purchase or in the Letter of Transmittal and, if given or made, such information or representation must not be relied upon as having been authorized. No broker, dealer, bank, trust company, fiduciary or other person shall be deemed to be an agent of Purchaser, the Depositary or the Information Agent for the purpose of the Offer. Neither delivery of this Offer to Purchase nor any purchase pursuant to the Offer will, under any circumstances, create any implication that there has been no change in the affairs of Parent, Purchaser, Forty Seven or any of their respective subsidiaries since the date as of which information is furnished or the date of this Offer to Purchase.

    Gilead Sciences, Inc.
Toro Merger Sub, Inc.
March 10, 2020

58


 SCHEDULE A

INFORMATION CONCERNING MEMBERS OF THE BOARDS OF DIRECTORS AND
THE EXECUTIVE OFFICERS OF PURCHASER AND PARENT.

1.     Directors and Executive Officers of Purchaser.

        The following table sets forth information about the directors and executive officers of Purchaser as of March 10, 2020.

Name, Country of Citizenship, Position
  Present Principal Occupation or Employment; Material Positions Held During the
Past Five Years; Certain Other Information

Andrew D. Dickinson
United States of America
President and Treasurer; Director

   Mr. Dickinson serves as Parent's Chief Financial Officer, responsible for the oversight of Parent's global finance, corporate development, information technology, operations and strategy organizations. Mr. Dickinson joined Parent in 2016 and prior to his current role, served as head of Parent's corporate development and strategy group. In that role, Mr. Dickinson drove all of Parent's licensing, partnership and acquisition transactions and guided investments into new areas. Prior to his tenure at Parent, Mr. Dickinson was the global Co-Head of Healthcare Investment Banking at Lazard. Earlier in his career, he served as General Counsel and Vice President of Corporate Development at Myogen, Inc., which was acquired by Parent in 2006. Mr. Dickinson received his bachelor's degree in molecular, cellular and developmental biology from the University of Colorado at Boulder and his law degree from Loyola University of Chicago.

Brett A. Pletcher
United States of America
Secretary; Director

  

Mr. Pletcher leads a group at Parent that includes the government affairs and policy, public affairs, and legal organizations. In his role, he oversees Parent's work to shape health policy and communicate Parent's perspective across external audiences. As General Counsel, he is also responsible for all of Parent's legal functions, including intellectual property, litigation and compliance efforts associated with the promotion of Parent's products. Before joining Parent in 2005, Mr. Pletcher was a partner in the law firm of Gunderson Dettmer, LLP, where he provided corporate and securities services to emerging growth public and private companies as well as venture capital investors. Mr. Pletcher received his bachelor's degree in economics and political science from the University of California, Riverside and earned his law degree from the University of California, Berkeley's Boalt Hall School of Law. He is a member of the California State Bar and a former member of the Nasdaq Listing and Hearing Review Council, and currently serves on the Advisory Board for the East Bay Community Law Center.

Schedule A-1

Name, Country of Citizenship, Position
  Present Principal Occupation or Employment; Material Positions Held During the
Past Five Years; Certain Other Information

Jason A. Okazaki
United States of America
Assistant Secretary; Director

  

Mr. Okazaki joined Parent in 2006 and is currently Senior Vice President, Legal and Assistant Secretary focusing primarily on legal support for Parent's corporate development, research and development, clinical/development operations, facilities, emerging markets, medical affairs, finance, human resources, information technology, and manufacturing organizations. Mr. Okazaki also serves as Assistant Secretary. Prior to joining Parent, Mr. Okazaki was a senior associate at the law firm of Skadden, Arps, Slate, Meagher & Flom, where he advised a wide range of clients on mergers and acquisitions and corporate securities matters. Mr. Okazaki received his bachelor's degree in economics from Stanford University and his law degree from the University of California, Hastings College of the Law.

2.     Directors and Executive Officers of Parent.

        The following table sets forth information about the directors and executive officers of Parent as of March 10, 2020.

Name, Country of Citizenship, Position
  Present Principal Occupation or Employment; Material Positions Held During the
Past Five Years; Certain Other Information

Jacqueline K. Barton, Ph.D.
United States of America
Director

   Dr. Barton is the John G. Kirkwood and Arthur A. Noyes Professor of Chemistry in the Division of Chemistry and Chemical Engineering at the California Institute of Technology, where she has been a member of the faculty for nearly 30 years and served as the Norman Davidson Leadership Chair of the division from 2009 to 2019. She is a member of the board of directors of Dow Inc., and previously served on the board of directors and Materials Advisory Committee of DowDupont Inc. and the board of directors of The Dow Chemical Company. Dr. Barton also founded and served on the board of directors of GeneOhm Sciences Inc., a molecular diagnostics company acquired by Becton, Dickinson and Company, and was a member of Parent's Scientific Advisory Board from 1989 to 2007. She is a member of the National Academy of Sciences, the National Academy of Medicine, and the American Philosophical Society. In 2011, Dr. Barton received the 2010 National Medal of Science for her discovery of new chemistry of the DNA helix, and in 2015, she received the Priestley Medal, the highest award of the American Chemical Society.

John F. Cogan, Ph.D.
United States of America
Director

  

Dr. Cogan is currently the Leonard and Shirley Ely Senior Fellow at the Hoover Institution at Stanford University, where he has had a continuing appointment since 1980. Dr. Cogan's current research is focused on U.S. budget and fiscal policy, social security and health care. Dr. Cogan has held a number of positions in the U.S. government, including Assistant Secretary for Policy in the U.S. Department of Labor and Associate Director and Deputy Director in the U.S. Office of Management and Budget. Dr. Cogan is a trustee of the Charles Schwab Family of Funds.

Schedule A-2

Name, Country of Citizenship, Position
  Present Principal Occupation or Employment; Material Positions Held During the
Past Five Years; Certain Other Information

Sandra J. Horning, M.D.
United States of America
Director

  

Dr. Horning was the Chief Medical Officer and Global Head of Product Development of Roche, Inc., until her retirement in 2019. During her 10-year career at Roche and Genentech, she helped bring 15 new medicines to patients in disease areas including cancer, multiple sclerosis, influenza and blindness. Prior to her career at Roche, Dr. Horning spent 25 years as a practicing oncologist, investigator and tenured professor at Stanford University School of Medicine, where she remains a professor of medicine emerita. From 2005 to 2006, she served as President of the American Society of Clinical Oncology. Dr. Horning was recognized as the 2020 Healthcare Businesswomen's Association Woman of the Year. She was also selected as the 2017 recipient of the Duane Roth Memorial Award, an honor dedicated to leaders in healthcare, whose work has overcome numerous scientific obstacles to create new paradigms in research and treatment. From 2015 to 2018, Dr. Horning served on the board of directors of Foundation Medicine. She currently serves as an advisor to EQRx.

Kelly A. Kramer
United States of America
Director

  

Ms. Kramer has been Executive Vice President and Chief Financial Officer of Cisco Systems, Inc., a worldwide technology leader, since 2015. Prior to that, she was Senior Vice President of Corporate Finance at Cisco. She previously served as Vice President and Chief Financial Officer of GE Healthcare Systems and Chief Financial Officer of GE Healthcare Biosciences. Ms. Kramer has also worked in GE's Corporate Headquarters, Transportation Systems and Aerospace divisions. She is a member of the board of directors of the Silicon Valley chapter of City Year, a non-profit organization that provides educational support for at-risk students in high-poverty communities.

Kevin E. Lofton
United States of America
Director

  

Mr. Lofton has served as Chief Executive Officer of CommonSpirit Health, a system of hospitals and other care centers that resulted from the merger between Catholic Health Initiatives ("CHI") and Dignity Health, since February 2019. Mr. Lofton recently announced that he will be retiring from this role effective June 30, 2020. He previously served as the Chief Executive Officer of CHI from 2003 to 2019. Mr. Lofton also served as Chief Executive Officer of two university hospitals, the University of Alabama at Birmingham Hospital and Howard University Hospital. In 2007, he served as Chairman of the Board of the American Hospital Association, the nation's largest hospital trade association. In 2016, he received an honorary Doctor of Humanities in Medicine degree from the Baylor College of Medicine. In 2014, the Healthcare Financial Management Association awarded the Richard L. Clarke Board of Directors Award to Mr. Lofton in recognition of his extensive and far reaching work in the area of healthcare disparities and creating healthier communities. Mr. Lofton also serves on the board of directors of Rite Aid Corporation.

Schedule A-3

Name, Country of Citizenship, Position
  Present Principal Occupation or Employment; Material Positions Held During the
Past Five Years; Certain Other Information

Harish Manwani
Singapore
Director

  

Mr. Manwani is a Senior Operating Partner at The Blackstone Group L.P., a leading global alternative asset manager, which he joined in 2015. He previously was Chief Operating Officer of the Unilever Group from 2011 until his retirement in 2014. Mr. Manwani joined Unilever in 1976 as a management trainee in India and held senior management roles around the world, including North America, Latin America, Asia, Africa and Central and Eastern Europe. Mr. Manwani is an honors graduate from Bombay University. He holds a master's degree in Management Studies, and he attended the Advanced Management Program at Harvard Business School. Mr. Manwani is the Chairman of Board of the Indian School of Business, and also serves on the board or directors of Whirlpool Corporation, Qualcomm Incorporated, Nielsen Holdings plc., EDBI Pte Ltd. and Tata Sons Private Limited. He previously served as the non-executive Chairman of Hindustan Unilever Limited from 2005 to 2018, and as a member of the board of directors of The Economic Development Board of Singapore from 2013 to 2019 and Pearson plc from 2013 to 2018.

Daniel P. O'Day
United States of America
Chief Executive Officer; Director

  

Mr. O'Day joined Parent as Chairman and Chief Executive Officer on March 1, 2019. Prior to joining Parent, Mr. O'Day served as the Chief Executive Officer of Roche Pharmaceuticals. His career at Roche spanned more than three decades, during which he held a number of executive positions in the company's pharmaceutical and diagnostics divisions in North America, Europe and Asia. During his time at Roche, Mr. O'Day demonstrated vision and leadership, helping to engineer the acquisitions of Flatiron Health and Foundation Medicine in 2018. He served as a member of Roche's Corporate Executive Committee, as well as on a number of public and private boards, including Genentech, Inc., Foundation Medicine, Inc. and Chugai Pharmaceutical Co., Ltd. Mr. O'Day holds a bachelor's degree in biology from Georgetown University and an MBA from Columbia University in New York.

Schedule A-4

Name, Country of Citizenship, Position
  Present Principal Occupation or Employment; Material Positions Held During the
Past Five Years; Certain Other Information

Richard J. Whitley, M.D.
United States of America
Director

  

Dr. Whitley is the Distinguished Professor, Loeb Scholar Chair in Pediatrics, and Professor of Pediatrics, Microbiology, Medicine and Neurosurgery at the University of Alabama at Birmingham. He is the Co-Director, Division of Pediatric Infectious Diseases; Vice-Chair, Department of Pediatrics; Senior Scientist, Department of Gene Therapy; Director for Drug Discovery and Development; Senior Leader, Comprehensive Cancer Center; Associate Director for Clinical Studies, Center for AIDS Research; and Co-Founder and Co-Director, Alabama Drug Discovery Alliance. Dr. Whitley is responsible for the National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group and directs a center for drug discovery in the arena of emerging infections. He is a past President of the International Society of Antiviral Research and the Infectious Diseases Society of America, and currently chairs both the NIAID Recombinant DNA Advisory Council and the NIAID HIV Vaccine Data Safety and Management Board. He is an elected member of the American Society of Clinical Investigation, the Association of American Physicians and an Honorary member of the Irish Academy of Science.

Gayle E. Wilson
United States of America
Director

  

Ms. Wilson served as California's First Lady from 1991 to 1999. She is a member of the board of directors of the Ralph M. Parsons Foundation, a non-profit organization that provides grants for higher education, social impact, civic, cultural issues and health issues. She is also Chair Emeritus of the Advisory Board of the California State Summer School for Math and Science and a member of the board of trustees of the California Institute of Technology.

Per Wold-Olsen
Norway
Director

  

Mr. Wold-Olsen has served as the Chair of Parent's Health Policy Advisory Board since 2007. From 2005 to 2006, he served as President of the Human Health Intercontinental Division of Merck & Co., Inc., a global pharmaceutical company. From 1997 until 2005, he served as President of Human Health Europe, Middle East/Africa and Worldwide Human Health Marketing for Merck. Mr. Wold-Olsen is currently Chairman of the Board of GN Store Nord A/S and Oncopeptides AB. In addition, he is the Chairman of the Board of the Medicines for Malaria Venture (MMV), a non-profit initiative dedicated to the discovery, development and delivery of new medicines for the treatment of malaria.

Schedule A-5

Name, Country of Citizenship, Position
  Present Principal Occupation or Employment; Material Positions Held During the
Past Five Years; Certain Other Information

Andrew D. Dickinson
United States of America
Chief Financial Officer

  

Mr. Dickinson serves as Parent's Chief Financial Officer, responsible for the oversight of Parent's global finance, corporate development, information technology, operations and strategy organizations. Mr. Dickinson joined Parent in 2016 and prior to his current role served as head of Parent's corporate development and strategy group. In that role, Mr. Dickinson drove all of Parent's licensing, partnership and acquisition transactions and guided investments into new areas. Prior to his tenure at Parent, Mr. Dickinson was the global Co-Head of Healthcare Investment Banking at Lazard. Earlier in his career, he served as General Counsel and Vice President of Corporate Development at Myogen, Inc., which was acquired by Parent in 2006. Mr. Dickinson received his bachelor's degree in molecular, cellular and developmental biology from the University of Colorado at Boulder and his law degree from Loyola University of Chicago.

Johanna Mercier
Canada
Chief Commercial Officer

  

Ms. Mercier leads Parent's Commercial organization with responsibility for commercializing Parent's therapies in countries and regions around the world. Prior to joining Parent in July 2019, Ms. Mercier spent 25 years at Bristol-Myers Squibb, where she was most recently President and Head of U.S., France, Germany, Japan, Korea and Taiwan. In her role, she oversaw a complex organization comprising a majority of the company's business. Ms. Mercier was also actively engaged with the policy and advocacy community to ensure the affordability and access of prescription medicines to patients. Ms. Mercier began her career in sales and marketing in Canada, then went on to lead worldwide early and clinical portfolios, followed by market teams across both the U.S. and Europe. She was Bristol-Myers Squibb's General Manager of UK & Ireland and later President of Worldwide Markets for Europe, Australia and Canada. In her most recent role, which included responsibility for the U.S. business and other priority markets, she successfully evolved the culture and drove strong commercial execution with double-digit growth and multiple launches that changed the standard of care in melanoma and renal cancers. Ms. Mercier holds a science degree from the University of Montreal and an MBA from Concordia University.

Schedule A-6

Name, Country of Citizenship, Position
  Present Principal Occupation or Employment; Material Positions Held During the
Past Five Years; Certain Other Information

Merdad V. Parsey, M.D., Ph.D.
United States of America
Chief Medical Officer

  

Dr. Parsey is Parent's Chief Medical Officer, responsible for overseeing Parent's global clinical development and medical affairs organizations. In his role, Dr. Parsey supervises all clinical trials and development operations. Together with the leadership team, he works to advance clinical development strategies and programs with the goal of changing the trajectory of disease and transforming care for the patients of today and tomorrow. Dr. Parsey joined Parent in 2019, after serving as Senior Vice President of Early Clinical Development at Genentech, where he led clinical development for areas including inflammation, oncology and infectious diseases. Prior to Genentech, Dr. Parsey served as President and CEO of 3-V Biosciences (now Sagimet BioSciences), held development roles at Sepracor, Regeneron and Merck and was Assistant Professor of Medicine and Director of Critical Care Medicine at the New York University School of Medicine. He completed his M.D. and Ph.D. at the University of Maryland, Baltimore, his residency in Internal Medicine at Stanford University and his fellowship in Pulmonary and Critical Care Medicine at the University of Colorado. Dr. Parsey currently serves on the Board of Directors for Sagimet BioSciences.

Brett A. Pletcher
United States of America
Executive Vice President, Corporate Affairs, General Counsel and Corporate Secretary

  

Mr. Pletcher leads a group at Parent that includes the government affairs and policy, public affairs, and legal organizations. In his role, he oversees Parent's work to shape health policy and communicate Parent's perspective across external audiences. As General Counsel, he is also responsible for all of Parent's legal functions, including intellectual property, litigation and compliance efforts associated with the promotion of Parent's products. Before joining Parent in 2005, Mr. Pletcher was a partner in the law firm of Gunderson Dettmer, LLP, where he provided corporate and securities services to emerging growth public and private companies as well as venture capital investors. Mr. Pletcher received his bachelor's degree in economics and political science from the University of California, Riverside and earned his law degree from the University of California, Berkeley's Boalt Hall School of Law. He is a member of the California State Bar and a former member of the Nasdaq Listing and Hearing Review Council, and currently serves on the Advisory Board for the East Bay Community Law Center.

Schedule A-7

        The common business address and telephone number for all the directors and executive officers is as follows:

        c/o Gilead Sciences, Inc., 333 Lakeside Drive, Foster City, California 94404, telephone number: (650) 574-3000.

        The Letter of Transmittal, certificates for Shares and any other required documents should be sent by each stockholder of Forty Seven or such stockholder's broker, dealer, commercial bank, trust company or other nominee to the Depositary as follows:

        The Depositary for the Offer is:

GRAPHIC

By Mail:
Computershare
c/o Voluntary Corporate Actions
P.O. Box 43011
Providence, RI 02940-3011		   By Overnight Courier:
Computershare
c/o Voluntary Corporate Actions
150 Royall Street, Suite V
Canton, MA 02021

        Any questions or requests for assistance may be directed to the Information Agent at its telephone number and location listed below. Requests for additional copies of this Offer to Purchase and the Letter of Transmittal may be directed to the Information Agent at its telephone number and location listed below. You may also contact your broker, dealer, commercial bank or trust company or other nominee for assistance concerning the Offer.

        The Information Agent for the Offer is:

GRAPHIC

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, NY 10022
Stockholders may call toll free:
(888) 750-5834 (from the U.S. and Canada)
or +1 (412) 232-3651 (from other locations)
Banks and Brokers may call collect: (212) 750-5833



QuickLinks

IMPORTANT
TABLE OF CONTENTS
SUMMARY TERM SHEET
INTRODUCTION
THE TENDER OFFER
SCHEDULE A INFORMATION CONCERNING MEMBERS OF THE BOARDS OF DIRECTORS AND THE EXECUTIVE OFFICERS OF PURCHASER AND PARENT.

QuickLinks -- Click here to rapidly navigate through this document

Exhibit (a)(1)(B)

LETTER OF TRANSMITTAL
To Tender Shares of Common Stock
of
FORTY SEVEN, INC.
a Delaware corporation
at
$95.50 NET PER SHARE
Pursuant to the Offer to Purchase
Dated March 10, 2020
by
TORO MERGER SUB, INC.
a wholly owned subsidiary of
GILEAD SCIENCES, INC.

        THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT ONE MINUTE
AFTER 11:59 P.M., EASTERN TIME, ON APRIL 6, 2020,
UNLESS THE OFFER IS EXTENDED OR EARLIER TERMINATED.


The Depositary for the Offer is:

LOGO

By Mail:
Computershare
c/o Voluntary Corporate Actions
P.O. Box 43011
Providence, RI 02940-3011		   By Overnight Courier:
Computershare
c/o Voluntary Corporate Actions
150 Royall Street, Suite V
Canton, MA 02021

Delivery of this Letter of Transmittal to an address other than as set forth above will not constitute a valid delivery to the Depositary (as defined below). You must sign this Letter of Transmittal in the appropriate space provided therefor below, with signature guaranteed, if required, and complete the Internal Revenue Service (the "IRS") Form W-9 included in this Letter of Transmittal, if required. Stockholders who are not United States persons should submit a properly completed and signed IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, or other appropriate IRS Form W-8. Failure to provide the information on IRS Form W-9 or an appropriate IRS Form W-8, as applicable, may subject you to United States federal income tax backup withholding on any payments made to you pursuant to the Offer (as defined below). The instructions set forth in this Letter of Transmittal should be read carefully before you tender any of your Shares (as defined below) into the Offer (as defined below).

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
    DESCRIPTION OF SHARES TENDERED    
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
                Shares Tendered            
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
    Name(s) and Address(es) of Registered Holder(s)
(Please fill in, if blank, exactly as name(s) appear(s)
on certificate(s)) (Attach additional signed list
if necessary)		       Certificate
Number(s)		       Total Number of
Shares Represented
by Certificate(s)		       Book Entry
Shares
Tendered		       Total Number
of Shares
Tendered*		    
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
                                             
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

 
 
 
 
 
 
 
 
Total Shares
 
 
 
 
 
 
 
 
 
 
 
 
 
 
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
    *   Unless otherwise indicated, it will be assumed that all Shares described in the chart above are being tendered. See Instruction 4.    
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
​

        The Offer is being made to all holders of the Shares. Purchaser is not aware of any jurisdiction in which the making of the Offer or the acceptance thereof would be prohibited by securities, "blue sky" or other valid laws of such jurisdiction. If Purchaser becomes aware of any U.S. state in which the making of the Offer or the acceptance of Shares pursuant thereto would not be in compliance with an administrative or judicial action taken pursuant to a U.S. state statute, Purchaser will make a good faith effort to comply with any such law. If, after such good faith effort, Purchaser cannot comply with any such law, the Offer will not be made to (nor will tenders be accepted from or on behalf of) the holders of Shares in such state. In any jurisdictions where applicable laws require the Offer to be made by a licensed broker or dealer, the Offer shall be deemed to be made on behalf of Purchaser by one or more registered brokers or dealers licensed under the laws of such jurisdiction to be designated by Purchaser.

        This Letter of Transmittal is to be used by stockholders of Forty Seven, Inc. ("Forty Seven") if certificates ("Certificates") for shares of common stock, par value $0.0001 per share (the "Shares"), of Forty Seven (the "Shares") are to be forwarded herewith or, unless an Agent's Message (as defined in Section 3 of the Offer to Purchase) is utilized, if delivery of Shares is to be made by book-entry transfer to an account maintained by Computershare Trust Company, N.A. at The Depositary Trust Company ("DTC") (as described in Section 2 of the Offer to Purchase and pursuant to the procedures set forth in Section 3 thereof).

        Stockholders whose Certificates are not immediately available, who cannot complete the procedure for book-entry transfer on a timely basis, or who cannot deliver all other required documents to the Depositary on or prior to the Expiration Date must tender their Shares according to the guaranteed delivery procedure set forth in Section 3 of the Offer to Purchase in order to participate in the Offer. Shares tendered by the Notice of Guaranteed Delivery (as defined below) will be excluded from the calculation of the Minimum Tender Condition (as defined in the Offer to Purchase), unless such Shares and other required documents are received by the Depositary on or prior to the Expiration Date. See Instruction 2. Delivery of documents to DTC does not constitute delivery to the Depositary.

        Additional Information If Certificates Have Been Lost, Destroyed or Stolen, Are Being Delivered By Book-Entry Transfer, or Are Being Delivered Pursuant to a Previous Notice of Guaranteed Delivery

        If Certificates you are tendering with this Letter of Transmittal have been lost, stolen, destroyed or mutilated, you should contact American Stock Transfer & Trust Company, LLC in its capacity as transfer agent (the "Transfer Agent"), toll-free at (800) 937-5449 regarding the requirements for replacement. You may be required to post a bond to secure against the risk that the Certificates may be subsequently recirculated. You are urged to contact the Transfer Agent immediately in order to receive further instructions, for a determination of whether you will need to post a bond and to permit timely processing of this documentation. See Instruction 11.

o
CHECK HERE IF TENDERED SHARES ARE BEING DELIVERED HEREWITH.

o
CHECK HERE IF YOU HAVE LOST YOUR CERTIFICATE(S) AND REQUIRE ASSISTANCE IN OBTAINING REPLACEMENT CERTIFICATE(S). BY CHECKING THIS BOX, YOU UNDERSTAND THAT YOU MUST CONTACT AMERICAN STOCK TRANSFER & TRUST COMPANY, LLC TO OBTAIN INSTRUCTIONS FOR REPLACING LOST CERTIFICATES. SEE INSTRUCTION 11.

o
CHECK HERE IF TENDERED SHARES ARE BEING DELIVERED BY BOOK-ENTRY TRANSFER MADE TO AN ACCOUNT MAINTAINED BY THE DEPOSITARY WITH DTC AND COMPLETE THE FOLLOWING (NOTE THAT ONLY FINANCIAL INSTITUTIONS
​

Voluntary Corporate Action: COY GILD    2

​

Name of Tendering Institution:    
​ ​ ​

 
DTC Account Number: ​      ​ Transaction Code Number: ​     
​ ​ ​ ​ ​ ​ ​
o
CHECK HERE IF TENDERED SHARES ARE BEING DELIVERED PURSUANT TO A NOTICE OF GUARANTEED DELIVERY PREVIOUSLY SENT TO THE DEPOSITARY AND COMPLETE THE FOLLOWING:
Name(s) of Tendering Stockholder(s):  

 

Window Ticket Number (if any):  

 

Date of Execution of Notice of Guaranteed Delivery:  

 

Name of Eligible Institution that Guaranteed Delivery:  
​

Voluntary Corporate Action: COY GILD    3

​


NOTE: SIGNATURES MUST BE PROVIDED BELOW.
PLEASE READ ACCOMPANYING INSTRUCTIONS CAREFULLY

Ladies and Gentlemen:

        The undersigned hereby tenders to Toro Merger Sub, Inc. ("Purchaser"), a Delaware corporation, and a wholly owned subsidiary of Gilead Sciences, Inc., a Delaware corporation ("Parent") the above described shares of common stock, par value $0.0001 per share (the "Shares"), of Forty Seven, Inc., a Delaware corporation ("Forty Seven"), pursuant to Purchaser's offer to purchase each outstanding Share that is validly tendered and not validly withdrawn, at a price of $95.50 per Share, net to the seller in cash, without interest and subject to any required withholding of taxes, upon the terms and subject to the conditions (including the Minimum Tender Condition) described in the Offer to Purchase, dated March 10, 2020 (the "Offer to Purchase"), and in this Letter of Transmittal (the "Letter of Transmittal" which, together with the Offer to Purchase, as each may be amended and supplemented from time to time, collectively constitute the "Offer"), receipt of which is hereby acknowledged.

        Upon the terms and subject to the conditions of the Offer (and if the Offer is extended or amended, the terms of any such extension or amendment), and effective upon acceptance for payment of the Shares tendered herewith and not validly withdrawn on or prior to the Expiration Date (as defined in Section 1 of the Offer to Purchase) in accordance with the terms of the Offer, the undersigned hereby sells, assigns and transfers to or upon the order of Purchaser all right, title and interest in and to all of the Shares that are being tendered hereby (and any and all dividends, distributions, rights, other Shares or other securities issued or issuable in respect thereof on or after the date hereof (collectively, "Distributions")) and irrevocably constitutes and appoints Computershare Trust Company, N.A. (the "Depositary") the true and lawful agent and attorney-in-fact of the undersigned with respect to such Shares (and any and all Distributions), with full power of substitution (such power of attorney being deemed to be an irrevocable power coupled with an interest in the Shares tendered by this Letter of Transmittal), to (i) deliver Certificates for such Shares (and any and all Distributions) or transfer ownership of such Shares (and any and all Distributions) on the account books maintained by The Depositary Trust Company ("DTC") or otherwise held in book-entry form, together, in any such case, with all accompanying evidences of transfer and authenticity, to or upon the order of Purchaser, (ii) present such Shares (and any and all Distributions) for transfer on the books of Forty Seven and (iii) receive all benefits and otherwise exercise all rights of beneficial ownership of such Shares (and any and all Distributions), all in accordance with the terms and subject to the conditions of the Offer.

        By executing this Letter of Transmittal (or taking action resulting in the delivery of an Agent's Message, as defined in Section 3 of the Offer to Purchase), the undersigned hereby irrevocably appoints each of the designees of Purchaser the attorneys-in-fact and proxies of the undersigned, each with full power of substitution, to (i) vote at any annual or special meeting of Forty Seven stockholders or any adjournment or postponement thereof or otherwise in such manner as each such attorney-in-fact and proxy or its, his or her substitute shall in its, his or her sole discretion deem proper with respect to, (ii) execute any written consent concerning any matter as each such attorney-in-fact and proxy or its, his or her substitute shall in its, his or her sole discretion deem proper with respect to and (iii) otherwise act as each such attorney-in-fact and proxy or its, his or her substitute shall in its, his or her sole discretion deem proper with respect to, all of the Shares (and any and all Distributions) tendered hereby and accepted for payment by Purchaser. This appointment will be effective if and when, and only to the extent that, Purchaser accepts such Shares for payment pursuant to the Offer. This power of attorney and proxy are irrevocable and are granted in consideration of the acceptance for payment of such Shares in accordance with the terms of the Offer. Such acceptance for payment shall, without further action, revoke any prior powers of attorney and proxies granted by the undersigned at any time with respect to such Shares (and any and all Distributions), and no subsequent

​

Voluntary Corporate Action: COY GILD    4

powers of attorney, proxies, consents or revocations may be given by the undersigned with respect thereto (and, if given, will not be deemed effective). Purchaser reserves the right to require that, in order for the Shares to be deemed validly tendered, immediately upon Purchaser's acceptance for payment of such Shares, Purchaser or its designees must be able to exercise full voting, consent and other rights with respect to such Shares (and any and all Distributions), including voting at any meeting of Forty Seven stockholders.

        The undersigned hereby represents and warrants that the undersigned has full power and authority to tender, sell, assign and transfer any and all of the Shares tendered hereby (and any and all Distributions) and that, when the same are accepted for payment by Purchaser, Purchaser will acquire good and unencumbered title to such Shares (and such Distributions), free and clear of all liens, restrictions, charges and encumbrances and the same will not be subject to any adverse claims. The undersigned hereby represents and warrants that the undersigned is the registered owner of the Shares, or the Certificate(s) have been endorsed to the undersigned in blank, or the undersigned is a participant in DTC whose name appears on a security position listing as the owner of the Shares. The undersigned will, upon request, execute and deliver any additional documents deemed by the Depositary or Purchaser to be necessary or desirable to complete the sale, assignment and transfer of the Shares tendered hereby (and any and all Distributions). In addition, the undersigned shall remit and transfer promptly to the Depositary for the account of Purchaser all Distributions in respect of any and all of the Shares tendered hereby, accompanied by appropriate documentation of transfer, and, pending such remittance and transfer or appropriate assurance thereof, Purchaser shall be entitled to all rights and privileges as owner of each such Distribution and may withhold the entire purchase price of the Shares tendered hereby or deduct from such purchase price the amount or value of such Distribution as determined by Purchaser in its sole discretion.

        All authority herein conferred or agreed to be conferred shall not be affected by, and shall survive the death or incapacity of the undersigned, and any obligation of the undersigned hereunder shall be binding upon the heirs, executors, administrators, personal representatives, trustees in bankruptcy, successors and assigns of the undersigned. Except as stated in the Offer to Purchase, this tender is irrevocable.

        The undersigned hereby acknowledges that delivery of any Certificate shall be effected, and risk of loss and title to such Certificate shall pass, only upon the proper delivery of such Certificate to the Depositary.

        The undersigned understands that the valid tender of Shares pursuant to any of the procedures described in the Offer to Purchase and in the instructions hereto will constitute the undersigned's acceptance of the terms and conditions of the Offer. Purchaser's acceptance of such Shares for payment will constitute a binding agreement between the undersigned and Purchaser upon the terms and subject to the conditions of the Offer (and if the Offer is extended or amended, the terms and conditions of such extension or amendment). The undersigned recognizes that under certain circumstances set forth in the Offer, Purchaser may not be required to accept for payment any Shares tendered hereby.

        Unless otherwise indicated under "Special Payment Instructions," a check will be issued for the purchase price of all Shares purchased and, if appropriate, Certificates not tendered or accepted for payment in the name(s) of the registered holder(s) appearing above under "Description of Shares Tendered" will be returned. Similarly, unless otherwise indicated under "Special Delivery Instructions," the check for the purchase price of all Shares purchased will be mailed and, if appropriate, any Certificates not tendered or not accepted for payment (and any accompanying documents, as appropriate) will be returned to the address(es) of the registered holder(s) appearing above under "Description of Shares Tendered." In the event that the boxes entitled "Special Payment Instructions" and "Special Delivery Instructions" are both completed, the check for the purchase price of all Shares

​

Voluntary Corporate Action: COY GILD    5

​

purchased will be issued and, if appropriate, any Certificates not tendered or not accepted for payment (and any accompanying documents, as appropriate) will be returned in the name(s) of, and deliver such check and, if appropriate, return any Certificates (and any accompanying documents, as appropriate) to, the person(s) so indicated. Unless otherwise indicated herein in the box entitled "Special Payment Instructions," any Shares tendered herewith that are not accepted for payment will be credited by book-entry transfer by crediting the account at DTC designated above. The undersigned recognizes that Purchaser has no obligation, pursuant to the "Special Payment Instructions," to transfer any Shares from the name of the registered holder thereof if Purchaser does not accept for payment any of the Shares so tendered.

​

Voluntary Corporate Action: COY GILD    6

​

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
     SPECIAL PAYMENT INSTRUCTIONS
(See Instructions 1, 5, 6 and 7)		           SPECIAL DELIVERY INSTRUCTIONS
(See Instructions 1, 5, 6 and 7)		    
     To be completed ONLY if the check for the purchase price of Shares accepted for payment and/or Certificates not tendered or not accepted for payment are to be issued in the name of someone other than the undersigned.
 
Issue check and/or certificates to:		           To be completed ONLY if the check for the purchase price of Shares accepted for payment and/or Certificates evidencing Shares not tendered or not accepted are to be mailed to someone other than the undersigned or to the undersigned at an address other than that shown above.
 
Mail check and/or Certificates to:		    
     Name:                        
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
        (Please Print)           Name:        
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
    Address:                   (Please Print)    
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
                    Address:        
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
                                
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
    (Include Zip Code)                    
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
                (Include Zip Code)    
                                
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
    (Taxpayer Identification No. (e.g., Social Security No.)) (Also Complete, as appropriate, IRS Form W-9 Included Below)                    
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

IMPORTANT
STOCKHOLDER: YOU MUST SIGN BELOW
(U.S. Holders: Please complete and return the IRS Form W-9 included below)
(Non-U.S. Holders: Please obtain, complete and return appropriate IRS Form W-8)

   

(Signature(s) of Holder(s) of Shares)

Dated:                                                       

Name(s): ​     
​ ​ ​
(Please Print)

 
Capacity (full title) (See Instruction 5): ​     
​ ​ ​

 
Address: ​     
​ ​ ​
(Include Zip Code)

 
Area Code and Telephone No.: ​     
​ ​ ​

 
Tax Identification No. (e.g., Social Security No.) (See IRS Form W-9 included below): ​     
​ ​ ​

(Must be signed by registered holder(s) exactly as name(s) appear(s) on Certificate(s) or on a security position listing or by person(s) authorized to become registered holder(s) by Certificates and documents transmitted herewith. If signature is by a trustee, executor, administrator, guardian, attorney-in-fact, agent, officer of a corporation or other person acting in a fiduciary or representative capacity, please set forth full title and see Instruction 5.)

​

Voluntary Corporate Action: COY GILD    7


 INSTRUCTIONS
FORMING PART OF THE TERMS AND CONDITIONS OF THE OFFER

        1.    Guarantee of Signatures.    No signature guarantee is required on this Letter of Transmittal (a) if this Letter of Transmittal is signed by the registered holder(s) (which term, for purposes of this Instruction, includes any participant in DTC's systems whose name appears on a security position listing as the owner of the Shares) of Shares tendered herewith, unless such registered holder has completed either the box entitled "Special Payment Instructions" or the box entitled "Special Delivery Instructions" on this Letter of Transmittal or (b) if such Shares are tendered for the account of a financial institution (including most commercial banks, savings and loan associations and brokerage houses) that is a member in good standing of the Securities Transfer Agents Medallion Program or any other "eligible guarantor institution," as such term is defined in Rule 17Ad-15 under the Securities Exchange Act of 1934, as amended (each, an "Eligible Institution"). In all other cases, including those referred to above, all signatures on this Letter of Transmittal must be guaranteed by an Eligible Institution. See Instruction 5.

        2.    Requirements of Tender.    No alternative, conditional or contingent tenders will be accepted. In order for Shares to be validly tendered pursuant to the Offer, one of the following procedures must be followed:

        For Shares held as physical certificates, the Certificates representing tendered Shares, a properly completed and duly executed Letter of Transmittal, together with any required signature guarantees, and any other documents required by this Letter of Transmittal, must be received by the Depositary at one of its addresses set forth on the front page of this Letter of Transmittal before the Expiration Date.

        For Shares held in book-entry form, either a properly completed and duly executed Letter of Transmittal, together with any required signature guarantees, or an Agent's Message in lieu of this Letter of Transmittal, and any other required documents, must be received by the Depositary at the appropriate address set forth on the front page of this Letter of Transmittal, and such Shares must be delivered according to the book-entry transfer procedures (as set forth in Section 3 of the Offer to Purchase) and a timely confirmation of a book-entry transfer of Shares into the Depositary's account at DTC (a "Book-Entry Confirmation") must be received by the Depositary, in each case before the Expiration Date.

        Stockholders whose Certificates are not immediately available, or who cannot complete the procedure for delivery by book-entry transfer prior to the Expiration Date or who cannot deliver all other required documents to the Depositary prior to the Expiration Date, may tender their Shares by properly completing and duly executing a notice of guaranteed delivery (a "Notice of Guaranteed Delivery") pursuant to the guaranteed delivery procedure set forth in Section 3 of the Offer to Purchase. Pursuant to such procedure: (i) such tender must be made by or through an Eligible Institution, (ii) a properly completed and duly executed Notice of Guaranteed Delivery, substantially in the form made available by Purchaser, must be received by the Depositary by the Expiration Date and (iii) Certificates (or a Book-Entry Confirmation) evidencing all tendered Shares, in proper form for transfer, in each case together with this Letter of Transmittal, properly completed and duly executed, together with any required signature guarantees (or, in the case of book-entry transfer of Shares, either this Letter of Transmittal or an Agent's Message in lieu of this Letter of Transmittal), and any other documents required by this Letter of Transmittal, must be received by the Depositary within two NASDAQ Global Select Market trading days after the date of execution of such Notice of Guaranteed Delivery. A Notice of Guaranteed Delivery may be delivered by overnight courier or mailed to the Depositary and must include a guarantee by an Eligible Institution in the form set forth in the form of Notice of Guaranteed Delivery made available by Purchaser. In the case of Shares held through DTC, the Notice of Guaranteed Delivery must be delivered to the Depositary by a participant by means of

​

Voluntary Corporate Action: COY GILD    8

the confirmation system of DTC. Shares tendered by the Notice of Guaranteed Delivery will be excluded from the calculation of the Minimum Tender Condition, unless such Shares and other required documents are received by the Depositary by the Expiration Date.

        The method of delivery of Shares, this Letter of Transmittal and all other required documents, including delivery through DTC, is at the election and risk of the tendering stockholder. Shares will be deemed delivered (and the risk of loss of Certificates will pass) only when actually received by the Depositary (including, in the case of a book-entry transfer, by Book-Entry Confirmation). If delivery is by mail, then registered mail with return receipt requested, properly insured, is recommended. In all cases, sufficient time should be allowed to ensure timely delivery.

        No fractional Shares will be purchased. By executing this Letter of Transmittal, the tendering stockholder waives any right to receive any notice of the acceptance for payment of Shares.

        3.    Inadequate Space.    If the space provided herein is inadequate, Certificate numbers, the number of Shares represented by such Certificates and/or the number of Shares tendered should be listed on a separate signed schedule attached hereto.

        4.    Partial Tenders (Not Applicable to Stockholders who Tender by Book-Entry Transfer).    If fewer than all the Shares represented by any Certificate delivered to the Depositary are to be tendered, fill in the number of Shares which are to be tendered in the box entitled "Total Number of Shares Tendered." In such case, a new Certificate for the remainder of the Shares represented by the old Certificate will be sent to the person(s) signing this Letter of Transmittal, unless otherwise provided in the appropriate box on this Letter of Transmittal, as promptly as practicable following the expiration or termination of the Offer. All Shares represented by Certificates delivered to the Depositary will be deemed to have been tendered unless otherwise indicated.

        5.    Signatures on Letter of Transmittal; Stock Powers and Endorsements.    

        (a)    Exact Signatures.    If this Letter of Transmittal is signed by the registered holder(s) of the Shares tendered hereby, the signature(s) must correspond with the name(s) as written on the face of the Certificates without alteration, enlargement or any change whatsoever.

        (b)    Joint Holders.    If any of the Shares tendered hereby are held of record by two or more persons, all such persons must sign this Letter of Transmittal.

        (c)    Different Names on Certificates.    If any of the Shares tendered hereby are registered in different names on different Certificates, it will be necessary to complete, sign and submit as many separate Letters of Transmittal as there are different registrations of Certificates.

        (d)    Endorsements.    If this Letter of Transmittal is signed by the registered holder(s) of the Shares tendered hereby, no endorsements of Certificates or separate stock powers are required unless payment of the purchase price is to be made, or Shares not tendered or not purchased are to be returned, in the name of any person other than the registered holder(s). Signatures on any such Certificates or stock powers must be guaranteed by an Eligible Institution.

        (e)    Stock Powers.    If this Letter of Transmittal is signed by a person other than the registered holder(s) of the Shares tendered hereby, Certificates must be endorsed or accompanied by appropriate stock powers, in either case, signed exactly as the name(s) of the registered holder(s) appear(s) on the Certificates for such Shares. Signature(s) on any such Certificates or stock powers must be guaranteed by an Eligible Institution. See Instruction 1.

        (f)    Evidence of Fiduciary or Representative Capacity.    If this Letter of Transmittal or any Certificate or stock power is signed by a trustee, executor, administrator, guardian, attorney-in-fact, officer of a corporation or other legal entity or other person acting in a fiduciary or representative capacity, such person should so indicate when signing, and proper evidence satisfactory to the

​

Voluntary Corporate Action: COY GILD    9

​

Depositary of the authority of such person so to act must be submitted. Proper evidence of authority includes a power of attorney, a letter of testamentary or a letter of appointment.

        6.    Stock Transfer Taxes.    Except as otherwise provided in this Instruction 6, Purchaser or any successor entity thereto will pay all stock transfer taxes with respect to the transfer and sale of any Shares to it pursuant to the Offer (for the avoidance of doubt, transfer taxes do not include U.S. federal income taxes or withholding taxes). If, however, consideration is to be paid to, or if Certificate(s) for Shares not tendered or not accepted for payment are to be registered in the name of, any person(s) other than the registered holder(s), or if tendered Certificate(s) for Share(s) are registered in the name of any person(s) other than the person(s) signing this Letter of Transmittal, Purchaser will not be responsible for any stock transfer or similar taxes (whether imposed on the registered holder(s) or such other person(s) or otherwise) payable on account of the transfer to such other person(s) and no consideration shall be paid in respect of such Share(s) unless evidence satisfactory to Purchaser of the payment of such taxes, or exemption therefrom, is submitted.

        7.    Special Payment and Delivery Instructions.    If a check is to be issued for the purchase price of any Shares tendered by this Letter of Transmittal in the name of, and, if appropriate, Certificates for Shares not tendered or not accepted for payment are to be issued or returned to, any person(s) other than the signer of this Letter of Transmittal or if a check and, if appropriate, such Certificates are to be returned to any person(s) other than the person(s) signing this Letter of Transmittal or to an address other than that shown in this Letter of Transmittal, the appropriate boxes on this Letter of Transmittal must be completed.

        8.    Tax Withholding.    Under U.S. federal income tax laws, the Depositary may be required to withhold a portion of any payments made to certain stockholders pursuant to the Offer. To avoid such backup withholding, a tendering stockholder that is a United States person (as defined for U.S. federal income tax purposes, a "United States person"), and, if applicable, each other U.S. payee, is required to (a) provide the Depositary with a correct Taxpayer Identification Number ("TIN") on IRS Form W-9, which is included herein, and to certify, under penalty of perjury, that such number is correct and that such stockholder or payee is not subject to backup withholding of federal income tax or (b) otherwise establish a basis for exemption from backup withholding. Failure to provide the information on the IRS Form W-9 may subject the tendering stockholder or payee to backup withholding at the applicable rate (currently 24%), and such stockholder or payee may be subject to a penalty imposed by the IRS. See the enclosed IRS Form W-9 and the instructions thereto for additional information.

        Certain stockholders or payees (including, among others, corporations) may not be subject to backup withholding. Exempt stockholders or payees that are United States persons should furnish their TIN, check the appropriate box on the IRS Form W-9 and sign, date and return the IRS Form W-9 to the Depositary in order to avoid backup withholding. A stockholder or other payee that is not a United States person may qualify as an exempt recipient by providing the Depositary with a properly completed IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, or other appropriate IRS Form W-8, signed under penalties of perjury, attesting to such stockholder or payee's foreign status or by otherwise establishing an exemption. An appropriate IRS Form W-8 may be obtained from the Depositary or the IRS website (www.irs.gov).

        Backup withholding is not an additional tax. Rather, the federal income tax liability of persons subject to backup withholding will be reduced by the amount of tax withheld. If backup withholding results in an overpayment of taxes, a refund or credit may be obtained from the IRS if eligibility is established and appropriate procedure is followed.

        9.    Irregularities.    All questions as to the validity, form, eligibility (including time of receipt) and acceptance for payment of any tender of Shares will be determined by Purchaser, in its sole discretion, which determination shall be final and binding on all parties. However, stockholders may challenge

​

Voluntary Corporate Action: COY GILD    10

​

Purchaser's determinations in a court of competent jurisdiction. Purchaser reserves the absolute right to reject any and all tenders determined by it not to be in proper form or the acceptance for payment of which may, in the opinion of its counsel, be unlawful. Purchaser also reserves the absolute right to waive any defect or irregularity in the tender of any Shares of any particular stockholder, whether or not similar defects or irregularities are waived in the case of other stockholders. No tender of Shares will be deemed to have been validly made until all defects and irregularities have been waived or cured within such time as Purchaser shall determine. None of Parent, Purchaser, the Depositary, the Information Agent or any other person will be under any duty to give notice of any defects or irregularities in tenders or incur any liability for failure to give any such notice. Purchaser's interpretation of the terms and conditions of the Offer (including the Letter of Transmittal and the instructions thereto) will be final and binding.

        10.    Questions and Requests for Additional Copies.    The Information Agent may be contacted at the address and telephone number set forth on the last page of this Letter of Transmittal for questions and/or requests for additional copies of the Offer to Purchase, this Letter of Transmittal, the Notice of Guaranteed Delivery and other tender offer materials. You may also contact your broker, dealer, commercial bank, trust company or other nominee for assistance. Such copies will be furnished promptly at Purchaser's expense.

        11.    Lost, Stolen Destroyed or Mutilated Certificates.    If any Certificate has been lost, stolen, destroyed or mutilated, the stockholder should promptly notify the Transfer Agent toll-free at (800) 937-5449. The stockholder will then be instructed as to the steps that must be taken in order to replace such Certificates. You may be required to post a bond to secure against the risk that the Certificates(s) may be subsequently recirculated. This Letter of Transmittal and related documents cannot be processed until the procedures for replacing lost, destroyed or stolen certificates have been followed. You are urged to contact the Transfer Agent immediately in order to receive further instructions and for a determination of whether you will need to post a bond and to permit timely processing of this documentation. This Letter of Transmittal and related documents cannot be processed until the procedures for replacing lost, destroyed, mutilated or stolen Certificates have been followed.

        Certificates evidencing tendered Shares, or a Book-Entry Confirmation into the Depositary's account at DTC, as well as this Letter of Transmittal, properly completed and duly executed, with any required signature guarantees, or an Agent's Message (if utilized in lieu of this Letter of Transmittal in connection with a book-entry transfer), and any other documents required by this Letter of Transmittal, must be received before the Expiration Date, or the tendering stockholder must comply with the procedures for guaranteed delivery.

CERTIFICATE OF TAXPAYER AWAITING IDENTIFICATION NUMBER

        I certify under the penalties of perjury that a taxpayer identification number has not been issued to me, and either (a) I have mailed or delivered an application to receive a taxpayer identification number to the appropriate Internal Revenue Service Center or Social Security Administration Office, or (b) I intend to mail or deliver an application in the near future. I understand that if I do not provide a taxpayer identification number to the Depositary or otherwise establish an exemption from backup withholding, 24% of all reportable payments made to me will be withheld, but will be refunded to me if I provide a certified taxpayer identification number within 60 days.

Signature:                                                                                         Date:                                                               

​

Voluntary Corporate Action: COY GILD    11

​


Form       W-9
(Rev. October 2018)
Department of the Treasury
Internal Revenue Service
 
 
 
Request for Taxpayer
Identification Number and Certification
  
> Go to www.irs.gov/FormW9 for instructions and the latest information.
 
 
 


  
Give Form to the
requester. Do not
send to the IRS.
    
​ ​ ​ ​ ​ ​ ​ ​ ​

Print or type.
See Specific Instructions on page 3.

 

  

1 Name (as shown on your income tax return). Name is required on this line; do not leave this line blank.
    
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

 

  

2 Business name/disregarded entity name, if different from above
    
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

 

  

3 Check appropriate box for federal tax classification of the person whose name is entered on line 1. Check only one of the following seven boxes.

o Individual/sole proprietor or    o C Corporation    o S Corporation    o Partnership    o Trust/estate
      single-member LLC

      

4 Exemptions (codes apply only to
certain entities, not individuals; see
instructions on page 3):

Exempt payee code (if any) _____


 
 


o Limited liability company. Enter the tax classification (C=C corporation, S=S corporation, P=Partnership) > _____
 
 
 
 


 
 


Note: Check the appropriate box in the line above for the tax classification of the single-member owner. Do not check LLC if the LLC is classified as a single-member LLC that is disregarded from the owner unless the owner of the LLC is another LLC that is not disregarded from the owner for U.S. federal tax purposes. Otherwise, a single-member LLC that is disregarded from the owner should check the appropriate box for the tax classification of its owner.
 
 
 
Exemption from FATCA reporting
 code (if any) _____

 

  

o Other (see instructions) >

      

(Applies to accounts maintained outside the U.S.)
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

 

  

5 Address (number, street, and apt. or suite no.) See instructions.
    

       Requester's name and address (optional)
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

 

  

6 City, state, and ZIP code
    

                
​   ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

 

  

7 List account number(s) here (optional)
    
​ ​ ​
  Part I   Taxpayer Identification Number (TIN)
​ ​ ​

Enter your TIN in the appropriate box. The TIN provided must match the name given on line 1 to avoid backup withholding. For individuals, this is generally your social security number (SSN). However, for a resident alien, sole proprietor, or disregarded entity, see the instructions for Part I, later. For other entities, it is your employer identification number (EIN). If you do not have a number, see How to get a TIN, later.

Note: If the account is in more than one name, see the instructions for line 1. Also see What Name and Number To Give the Requester for guidelines on whose number to enter.


 
​
Social security number
​
 
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
  ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​  
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
  ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​  
  ​   ​   ​   ​   ​   ​   ​ – ​   ​   ​   ​   ​   ​ – ​   ​   ​   ​   ​   ​   ​   ​   ​  
  ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​  
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
or ​   ​  
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

 
​
Employer identification number
​
 
​
 
​
 
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
  ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​  
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
  ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​  
  ​   ​   ​   ​   ​ – ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​  
  ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​  
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
​ ​ ​
  Part II   Certification
​ ​ ​

Under penalties of perjury, I certify that:

1.   The number shown on this form is my correct taxpayer identification number (or I am waiting for a number to be issued to me); and

2.
 
I am not subject to backup withholding because: (a) I am exempt from backup withholding, or (b) I have not been notified by the Internal Revenue Service (IRS) that I am subject to backup withholding as a result of a failure to report all interest or dividends, or (c) the IRS has notified me that I am no longer subject to backup withholding; and

3.
 
I am a U.S. citizen or other U.S. person (defined below); and

4.
 
The FATCA code(s) entered on this form (if any) indicating that I am exempt from FATCA reporting is correct.

Certification instructions. You must cross out item 2 above if you have been notified by the IRS that you are currently subject to backup withholding because you have failed to report all interest and dividends on your tax return. For real estate transactions, item 2 does not apply. For mortgage interest paid, acquisition or abandonment of secured property, cancellation of debt, contributions to an individual retirement arrangement (IRA), and generally, payments other than interest and dividends, you are not required to sign the certification, but you must provide your correct TIN. See the instructions for Part II, later.

​ ​ ​ ​ ​ ​ ​
Sign
Here		       Signature of
U.S. person >		   Date >
​ ​ ​ ​ ​ ​ ​

 


General Instructions

Section references are to the Internal Revenue Code unless otherwise noted.

Future developments. For the latest information about developments related to Form W-9 and its instructions, such as legislation enacted after they were published, go to www.irs.gov/FormW9.

Purpose of Form

An individual or entity (Form W-9 requester) who is required to file an information return with the IRS must obtain your correct taxpayer identification number (TIN) which may be your social security number (SSN), individual taxpayer identification number (ITIN), adoption taxpayer identification number (ATIN), or employer identification number (EIN), to report on an information return the amount paid to you, or other amount reportable on an information return. Examples of information returns include, but are not limited to, the following.

• Form 1099-INT (interest earned or paid)

• Form 1099-DIV (dividends, including those from stocks or mutual funds)

• Form 1099-MISC (various types of income, prizes, awards, or gross proceeds)

• Form 1099-B (stock or mutual fund sales and certain other transactions by brokers)

• Form 1099-S (proceeds from real estate transactions)

• Form 1099-K (merchant card and third party network transactions)

• Form 1098 (home mortgage interest), 1098-E (student loan interest), 1098-T (tuition)

• Form 1099-C (canceled debt)

• Form 1099-A (acquisition or abandonment of secured property)

     Use Form W-9 only if you are a U.S. person (including a resident alien), to provide your correct TIN.

     If you do not return Form W-9 to the requester with a TIN, you might be subject to backup withholding. See What is backup withholding, later.

​ ​ ​ ​ ​
    Cat. No. 10231X   Form W-9 (Rev. 10-2018)

Form W-9 (Rev. 10-2018)   Page 2
 

 

     By signing the filled-out form, you:

     1. Certify that the TIN you are giving is correct (or you are waiting for a number to be issued),

     2. Certify that you are not subject to backup withholding, or

     3. Claim exemption from backup withholding if you are a U.S. exempt payee. If applicable, you are also certifying that as a U.S. person, your allocable share of any partnership income from a U.S. trade or business is not subject to the withholding tax on foreign partners' share of effectively connected income, and

     4. Certify that FATCA code(s) entered on this form (if any) indicating that you are exempt from the FATCA reporting, is correct. See What is FATCA reporting, later, for further information.

Note: If you are a U.S. person and a requester gives you a form other than Form W-9 to request your TIN, you must use the requester's form if it is substantially similar to this Form W-9.

Definition of a U.S. person. For federal tax purposes, you are considered a U.S. person if you are:

• An individual who is a U.S. citizen or U.S. resident alien;

• A partnership, corporation, company, or association created or organized in the United States or under the laws of the United States;

• An estate (other than a foreign estate); or

• A domestic trust (as defined in Regulations section 301.7701-7).

Special rules for partnerships. Partnerships that conduct a trade or business in the United States are generally required to pay a withholding tax under section 1446 on any foreign partners' share of effectively connected taxable income from such business. Further, in certain cases where a Form W-9 has not been received, the rules under section 1446 require a partnership to presume that a partner is a foreign person, and pay the section 1446 withholding tax. Therefore, if you are a U.S. person that is a partner in a partnership conducting a trade or business in the United States, provide Form W-9 to the partnership to establish your U.S. status and avoid section 1446 withholding on your share of partnership income.

     In the cases below, the following person must give Form W-9 to the partnership for purposes of establishing its U.S. status and avoiding withholding on its allocable share of net income from the partnership conducting a trade or business in the United States.

• In the case of a disregarded entity with a U.S. owner, the U.S. owner of the disregarded entity and not the entity;

• In the case of a grantor trust with a U.S. grantor or other U.S. owner, generally, the U.S. grantor or other U.S. owner of the grantor trust and not the trust; and

• In the case of a U.S. trust (other than a grantor trust), the U.S. trust (other than a grantor trust) and not the beneficiaries of the trust.

Foreign person. If you are a foreign person or the U.S. branch of a foreign bank that has elected to be treated as a U.S. person, do not use Form W-9. Instead, use the appropriate Form W-8 or Form 8233 (see Pub. 515, Withholding of Tax on Nonresident Aliens and Foreign Entities).

Nonresident alien who becomes a resident alien. Generally, only a nonresident alien individual may use the terms of a tax treaty to reduce or eliminate U.S. tax on certain types of income. However, most tax treaties contain a provision known as a "saving clause." Exceptions specified in the saving clause may permit an exemption from tax to continue for certain types of income even after the payee has otherwise become a U.S. resident alien for tax purposes.

     If you are a U.S. resident alien who is relying on an exception contained in the saving clause of a tax treaty to claim an exemption from U.S. tax on certain types of income, you must attach a statement to Form W-9 that specifies the following five items.

     1. The treaty country. Generally, this must be the same treaty under which you claimed exemption from tax as a nonresident alien.

     2. The treaty article addressing the income.

     3. The article number (or location) in the tax treaty that contains the saving clause and its exceptions.

     4. The type and amount of income that qualifies for the exemption from tax.

     5. Sufficient facts to justify the exemption from tax under the terms of the treaty article.

     Example. Article 20 of the U.S.-China income tax treaty allows an exemption from tax for scholarship income received by a Chinese student temporarily present in the United States. Under U.S. law, this student will become a resident alien for tax purposes if his or her stay in the United States exceeds 5 calendar years. However, paragraph 2 of the first Protocol to the U.S.-China treaty (dated April 30, 1984) allows the provisions of Article 20 to continue to apply even after the Chinese student becomes a resident alien of the United States. A Chinese student who qualifies for this exception (under paragraph 2 of the first protocol) and is relying on this exception to claim an exemption from tax on his or her scholarship or fellowship income would attach to Form W-9 a statement that includes the information described above to support that exemption.

     If you are a nonresident alien or a foreign entity, give the requester the appropriate completed Form W-8 or Form 8233.

Backup Withholding

What is backup withholding? Persons making certain payments to you must under certain conditions withhold and pay to the IRS 24% of such payments. This is called "backup withholding." Payments that may be subject to backup withholding include interest, tax-exempt interest, dividends, broker and barter exchange transactions, rents, royalties, nonemployee pay, payments made in settlement of payment card and third party network transactions, and certain payments from fishing boat operators. Real estate transactions are not subject to backup withholding.

     You will not be subject to backup withholding on payments you receive if you give the requester your correct TIN, make the proper certifications, and report all your taxable interest and dividends on your tax return.

Payments you receive will be subject to backup withholding if:

     1. You do not furnish your TIN to the requester,

     2. You do not certify your TIN when required (see the instructions for Part II for details),

     3. The IRS tells the requester that you furnished an incorrect TIN,

     4. The IRS tells you that you are subject to backup withholding because you did not report all your interest and dividends on your tax return (for reportable interest and dividends only), or

     5. You do not certify to the requester that you are not subject to backup withholding under 4 above (for reportable interest and dividend accounts opened after 1983 only).

     Certain payees and payments are exempt from backup withholding. See Exempt payee code, later, and the separate Instructions for the Requester of Form W-9 for more information.

     Also see Special rules for partnerships, earlier.

What is FATCA Reporting?

The Foreign Account Tax Compliance Act (FATCA) requires a participating foreign financial institution to report all United States account holders that are specified United States persons. Certain payees are exempt from FATCA reporting. See Exemption from FATCA reporting code, later, and the Instructions for the Requester of Form W-9 for more information.

Updating Your Information

You must provide updated information to any person to whom you claimed to be an exempt payee if you are no longer an exempt payee and anticipate receiving reportable payments in the future from this person. For example, you may need to provide updated information if you are a C corporation that elects to be an S corporation, or if you no longer are tax exempt. In addition, you must furnish a new Form W-9 if the name or TIN changes for the account; for example, if the grantor of a grantor trust dies.

Penalties

Failure to furnish TIN. If you fail to furnish your correct TIN to a requester, you are subject to a penalty of $50 for each such failure unless your failure is due to reasonable cause and not to willful neglect.

Civil penalty for false information with respect to withholding. If you make a false statement with no reasonable basis that results in no backup withholding, you are subject to a $500 penalty.

Form W-9 (Rev. 10-2018)   Page 3
 

 

Criminal penalty for falsifying information. Willfully falsifying certifications or affirmations may subject you to criminal penalties including fines and/or imprisonment.

Misuse of TINs. If the requester discloses or uses TINs in violation of federal law, the requester may be subject to civil and criminal penalties.

Specific Instructions

Line 1

You must enter one of the following on this line; do not leave this line blank. The name should match the name on your tax return.

     If this Form W-9 is for a joint account (other than an account maintained by a foreign financial institution (FFI)), list first, and then circle, the name of the person or entity whose number you entered in Part I of Form W-9. If you are providing Form W-9 to an FFI to document a joint account, each holder of the account that is a U.S. person must provide a Form W-9.

     a. Individual. Generally, enter the name shown on your tax return. If you have changed your last name without informing the Social Security Administration (SSA) of the name change, enter your first name, the last name as shown on your social security card, and your new last name.

Note: ITIN applicant: Enter your individual name as it was entered on your Form W-7 application, line 1a. This should also be the same as the name you entered on the Form 1040/1040A/1040EZ you filed with your application.

     b. Sole proprietor or single-member LLC. Enter your individual name as shown on your 1040/1040A/1040EZ on line 1. You may enter your business, trade, or "doing business as" (DBA) name on line 2.

     c. Partnership, LLC that is not a single-member LLC, C corporation, or S corporation. Enter the entity's name as shown on the entity's tax return on line 1 and any business, trade, or DBA name on line 2.

     d. Other entities. Enter your name as shown on required U.S. federal tax documents on line 1. This name should match the name shown on the charter or other legal document creating the entity. You may enter any business, trade, or DBA name on line 2.

     e. Disregarded entity. For U.S. federal tax purposes, an entity that is disregarded as an entity separate from its owner is treated as a "disregarded entity." See Regulations section 301.7701-2(c)(2)(iii). Enter the owner's name on line 1. The name of the entity entered on line 1 should never be a disregarded entity. The name on line 1 should be the name shown on the income tax return on which the income should be reported. For example, if a foreign LLC that is treated as a disregarded entity for U.S. federal tax purposes has a single owner that is a U.S. person, the U.S. owner's name is required to be provided on line 1. If the direct owner of the entity is also a disregarded entity, enter the first owner that is not disregarded for federal tax purposes. Enter the disregarded entity's name on line 2, "Business name/disregarded entity name." If the owner of the disregarded entity is a foreign person, the owner must complete an appropriate Form W-8 instead of a Form W-9. This is the case even if the foreign person has a U.S. TIN.

Line 2

If you have a business name, trade name, DBA name, or disregarded entity name, you may enter it on line 2.

Line 3

Check the appropriate box on line 3 for the U.S. federal tax classification of the person whose name is entered on line 1. Check only one box on line 3.

​ ​ ​ ​ ​ ​ ​ ​ ​
    IF the entity/person on line 1 is a(n) . . .       THEN check the box for . . .    
​ ​ ​ ​ ​ ​ ​ ​ ​
    • Corporation       Corporation    
​ ​ ​ ​ ​ ​ ​ ​ ​
    • Individual
• Sole proprietorship, or
• Single-member limited liability company (LLC) owned by an individual and disregarded for U.S. federal tax purposes.		       Individual/sole proprietor or single-member LLC    
​ ​ ​ ​ ​ ​ ​ ​ ​
    • LLC treated as a partnership for U.S. federal tax purposes,
• LLC that has filed Form 8832 or 2553 to be taxed as a corporation, or
• LLC that is disregarded as an entity separate from its owner but the owner is another LLC that is not disregarded for U.S. federal tax purposes.		       Limited liability company and enter the appropriate tax classification. (P= Partnership; C= C corporation; or S= S corporation)    
​ ​ ​ ​ ​ ​ ​ ​ ​
    • Partnership       Partnership    
​ ​ ​ ​ ​ ​ ​ ​ ​
    • Trust/estate       Trust/estate    
​ ​ ​ ​ ​ ​ ​ ​ ​

Line 4, Exemptions

If you are exempt from backup withholding and/or FATCA reporting, enter in the appropriate space on line 4 any code(s) that may apply to you.

Exempt payee code.

• Generally, individuals (including sole proprietors) are not exempt from backup withholding.

• Except as provided below, corporations are exempt from backup withholding for certain payments, including interest and dividends.

• Corporations are not exempt from backup withholding for payments made in settlement of payment card or third party network transactions.

• Corporations are not exempt from backup withholding with respect to attorneys' fees or gross proceeds paid to attorneys, and corporations that provide medical or health care services are not exempt with respect to payments reportable on Form 1099-MISC.

     The following codes identify payees that are exempt from backup withholding. Enter the appropriate code in the space in line 4.

     1 – An organization exempt from tax under section 501(a), any IRA, or a custodial account under section 403(b)(7) if the account satisfies the requirements of section 401(f)(2)

     2 – The United States or any of its agencies or instrumentalities

     3 – A state, the District of Columbia, a U.S. commonwealth or possession, or any of their political subdivisions or instrumentalities

     4 – A foreign government or any of its political subdivisions, agencies, or instrumentalities

     5 – A corporation

     6 – A dealer in securities or commodities required to register in the United States, the District of Columbia, or a U.S. commonwealth or possession

     7 – A futures commission merchant registered with the Commodity Futures Trading Commission

     8 – A real estate investment trust

     9 – An entity registered at all times during the tax year under the Investment Company Act of 1940

     10 – A common trust fund operated by a bank under section 584(a)

     11 – A financial institution

     12 – A middleman known in the investment community as a nominee or custodian

     13 – A trust exempt from tax under section 664 or described in section 4947

Form W-9 (Rev. 10-2018)   Page 4
 

 

     The following chart shows types of payments that may be exempt from backup withholding. The chart applies to the exempt payees listed above, 1 through 13.

​ ​ ​ ​ ​
IF the payment is for . . .       THEN the payment is exempt for . . .
​ ​ ​ ​ ​
Interest and dividend payments       All exempt payees except for 7
​ ​ ​ ​ ​
Broker transactions       Exempt payees 1 through 4 and 6 through 11 and all C corporations. S corporations must not enter an exempt payee code because they are exempt only for sales of noncovered securities acquired prior to 2012.
​ ​ ​ ​ ​
Barter exchange transactions and patronage dividends       Exempt payees 1 through 4
​ ​ ​ ​ ​
Payments over $600 required to be reported and direct sales over $5,0001       Generally, exempt payees 1 through 52
​ ​ ​ ​ ​
Payments made in settlement of payment card or third party network transactions       Exempt payees 1 through 4
​ ​ ​ ​ ​

1 See Form 1099-MISC, Miscellaneous Income, and its instructions.

2 However, the following payments made to a corporation and reportable on Form 1099-MISC are not exempt from backup withholding: medical and health care payments, attorneys' fees, gross proceeds paid to an attorney reportable under section 6045(f), and payments for services paid by a federal executive agency.

Exemption from FATCA reporting code. The following codes identify payees that are exempt from reporting under FATCA. These codes apply to persons submitting this form for accounts maintained outside of the United States by certain foreign financial institutions. Therefore, if you are only submitting this form for an account you hold in the United States, you may leave this field blank. Consult with the person requesting this form if you are uncertain if the financial institution is subject to these requirements. A requester may indicate that a code is not required by providing you with a Form W-9 with "Not Applicable" (or any similar indication) written or printed on the line for a FATCA exemption code.

     A – An organization exempt from tax under section 501(a) or any individual retirement plan as defined in section 7701(a)(37)

     B – The United States or any of its agencies or instrumentalities

     C – A state, the District of Columbia, a U.S. commonwealth or possession, or any of their political subdivisions or instrumentalities

     D – A corporation the stock of which is regularly traded on one or more established securities markets, as described in Regulations section 1.1472-1(c)(1)(i)

     E – A corporation that is a member of the same expanded affiliated group as a corporation described in Regulations section 1.1472-1(c)(1)(i)

     F – A dealer in securities, commodities, or derivative financial instruments (including notional principal contracts, futures, forwards, and options) that is registered as such under the laws of the United States or any state

     G – A real estate investment trust

     H – A regulated investment company as defined in section 851 or an entity registered at all times during the tax year under the Investment Company Act of 1940

     I – A common trust fund as defined in section 584(a)

     J – A bank as defined in section 581

     K – A broker

     L – A trust exempt from tax under section 664 or described in section 4947(a)(1)

     M – A tax exempt trust under a section 403(b) plan or section 457(g) plan

Note: You may wish to consult with the financial institution requesting this form to determine whether the FATCA code and/or exempt payee code should be completed.

Line 5

Enter your address (number, street, and apartment or suite number). This is where the requester of this Form W-9 will mail your information returns. If this address differs from the one the requester already has on file, write NEW at the top. If a new address is provided, there is still a chance the old address will be used until the payor changes your address in their records.

Line 6

Enter your city, state, and ZIP code.

Part I. Taxpayer Identification Number (TIN)

Enter your TIN in the appropriate box. If you are a resident alien and you do not have and are not eligible to get an SSN, your TIN is your IRS individual taxpayer identification number (ITIN). Enter it in the social security number box. If you do not have an ITIN, see How to get a TIN below.

     If you are a sole proprietor and you have an EIN, you may enter either your SSN or EIN.

     If you are a single-member LLC that is disregarded as an entity separate from its owner, enter the owner's SSN (or EIN, if the owner has one). Do not enter the disregarded entity's EIN. If the LLC is classified as a corporation or partnership, enter the entity's EIN.

Note: See What Name and Number To Give the Requester, later, for further clarification of name and TIN combinations.

How to get a TIN. If you do not have a TIN, apply for one immediately. To apply for an SSN, get Form SS-5, Application for a Social Security Card, from your local SSA office or get this form online at www.SSA.gov. You may also get this form by calling 1-800-772-1213. Use Form W-7, Application for IRS Individual Taxpayer Identification Number, to apply for an ITIN, or Form SS-4, Application for Employer Identification Number, to apply for an EIN. You can apply for an EIN online by accessing the IRS website at www.irs.gov/Businesses and clicking on Employer Identification Number (EIN) under Starting a Business. Go to www.irs.gov/Forms to view, download, or print Form W-7 and/or Form SS-4. Or, you can go to www.irs.gov/OrderForms to place an order and have Form W-7 and/or SS-4 mailed to you within 10 business days.

     If you are asked to complete Form W-9 but do not have a TIN, apply for a TIN and write "Applied For" in the space for the TIN, sign and date the form, and give it to the requester. For interest and dividend payments, and certain payments made with respect to readily tradable instruments, generally you will have 60 days to get a TIN and give it to the requester before you are subject to backup withholding on payments. The 60-day rule does not apply to other types of payments. You will be subject to backup withholding on all such payments until you provide your TIN to the requester.

Note: Entering "Applied For" means that you have already applied for a TIN or that you intend to apply for one soon.

Caution: A disregarded U.S. entity that has a foreign owner must use the appropriate Form W-8.

Part II. Certification

To establish to the withholding agent that you are a U.S. person, or resident alien, sign Form W-9. You may be requested to sign by the withholding agent even if item 1, 4, or 5 below indicates otherwise.

     For a joint account, only the person whose TIN is shown in Part I should sign (when required). In the case of a disregarded entity, the person identified on line 1 must sign. Exempt payees, see Exempt payee code, earlier.

Signature requirements. Complete the certification as indicated in items 1 through 5 below.

Form W-9 (Rev. 10-2018)   Page 5
 

 

     1. Interest, dividend, and barter exchange accounts opened before 1984 and broker accounts considered active during 1983. You must give your correct TIN, but you do not have to sign the certification.

     2. Interest, dividend, broker, and barter exchange accounts opened after 1983 and broker accounts considered inactive during 1983. You must sign the certification or backup withholding will apply. If you are subject to backup withholding and you are merely providing your correct TIN to the requester, you must cross out item 2 in the certification before signing the form.

     3. Real estate transactions. You must sign the certification. You may cross out item 2 of the certification.

     4. Other payments. You must give your correct TIN, but you do not have to sign the certification unless you have been notified that you have previously given an incorrect TIN. "Other payments" include payments made in the course of the requester's trade or business for rents, royalties, goods (other than bills for merchandise), medical and health care services (including payments to corporations), payments to a nonemployee for services, payments made in settlement of payment card and third party network transactions, payments to certain fishing boat crew members and fishermen, and gross proceeds paid to attorneys (including payments to corporations).

     5. Mortgage interest paid by you, acquisition or abandonment of secured property, cancellation of debt, qualified tuition program payments (under section 529), ABLE accounts (under section 529A), IRA, Coverdell ESA, Archer MSA or HSA contributions or distributions, and pension distributions. You must give your correct TIN, but you do not have to sign the certification.

What Name and Number To Give the Requester

​ ​ ​ ​ ​ ​ ​
For this type of account:       Give name and SSN of:
​ ​ ​ ​ ​ ​ ​
1.   Individual       The individual
2.   Two or more individuals (joint account) other than an account maintained by an FFI       The actual owner of the account or, if combined funds, the first individual on the account1
3.   Two or more U.S. persons (joint account maintained by an FFI)       Each holder of the account
4.   Custodial account of a minor (Uniform Gift to Minors Act)       The minor2
5.   a. The usual revocable savings trust (grantor is also trustee)       The grantor-trustee1
    b. So-called trust account that is not a legal or valid trust under state law       The actual owner1
6.   Sole proprietorship or disregarded entity owned by an individual       The owner3
7.   Grantor trust filing under Optional Form 1099 Filing Method 1 (see Regulations section 1.671-4(b)(2)(i)(A))       The grantor*
​ ​ ​ ​ ​ ​ ​
For this type of account:       Give name and EIN of:
​ ​ ​ ​ ​ ​ ​
8.   Disregarded entity not owned by an individual       The owner
9.   A valid trust, estate, or pension trust       Legal entity4
10.   Corporation or LLC electing corporate status on Form 8832 or Form 2553       The corporation
11.   Association, club, religious, charitable, educational, or other tax-exempt organization       The organization
12.   Partnership or multi-member LLC       The partnership
13.   A broker or registered nominee       The broker or nominee
​ ​ ​ ​ ​ ​ ​
For this type of account:       Give name and EIN of:
​ ​ ​ ​ ​ ​ ​
14.   Account with the Department of Agriculture in the name of a public entity (such as a state or local government, school district, or prison) that receives agricultural program payments       The public entity

15.
 
Grantor trust filing under the Form 1041 Filing Method or the Optional Form 1099 Filing Method 2 (see Regulations section 1.671-4(b)(2)(i)(B))
 
 
 
The trust
​ ​ ​ ​ ​ ​ ​

1 List first and circle the name of the person whose number you furnish. If only one person on a joint account has an SSN, that person's number must be furnished.

2 Circle the minor's name and furnish the minor's SSN.

3 You must show your individual name and you may also enter your business or DBA name on the "Business name/disregarded entity" name line. You may use either your SSN or EIN (if you have one), but the IRS encourages you to use your SSN.

4 List first and circle the name of the trust, estate, or pension trust. (Do not furnish the TIN of the personal representative or trustee unless the legal entity itself is not designated in the account title.) Also see Special rules for partnerships, earlier.

* Note: The grantor also must provide a Form W-9 to trustee of trust.

Note: If no name is circled when more than one name is listed, the number will be considered to be that of the first name listed.

Secure Your Tax Records From Identity Theft

Identity theft occurs when someone uses your personal information such as your name, SSN, or other identifying information, without your permission, to commit fraud or other crimes. An identity thief may use your SSN to get a job or may file a tax return using your SSN to receive a refund.

     To reduce your risk:

• Protect your SSN,

• Ensure your employer is protecting your SSN, and

• Be careful when choosing a tax preparer.

     If your tax records are affected by identity theft and you receive a notice from the IRS, respond right away to the name and phone number printed on the IRS notice or letter.

     If your tax records are not currently affected by identity theft but you think you are at risk due to a lost or stolen purse or wallet, questionable credit card activity or credit report, contact the IRS Identity Theft Hotline at 1-800-908-4490 or submit Form 14039.

     For more information, see Pub. 5027, Identity Theft Information for Taxpayers.

     Victims of identity theft who are experiencing economic harm or a systemic problem, or are seeking help in resolving tax problems that have not been resolved through normal channels, may be eligible for Taxpayer Advocate Service (TAS) assistance. You can reach TAS by calling the TAS toll-free case intake line at 1-877-777-4778 or TTY/TDD 1-800-829-4059.

Protect yourself from suspicious emails or phishing schemes. Phishing is the creation and use of email and websites designed to mimic legitimate business emails and websites. The most common act is sending an email to a user falsely claiming to be an established legitimate enterprise in an attempt to scam the user into surrendering private information that will be used for identity theft.

Form W-9 (Rev. 10-2018)   Page 6
 

 

     The IRS does not initiate contacts with taxpayers via emails. Also, the IRS does not request personal detailed information through email or ask taxpayers for the PIN numbers, passwords, or similar secret access information for their credit card, bank, or other financial accounts.

     If you receive an unsolicited email claiming to be from the IRS, forward this message to phishing@irs.gov. You may also report misuse of the IRS name, logo, or other IRS property to the Treasury Inspector General for Tax Administration (TIGTA) at 1-800-366-4484. You can forward suspicious emails to the Federal Trade Commission at spam@uce.gov or report them at www.ftc.gov/complaint. You can contact the FTC at www.ftc.gov/idtheft or 877-IDTHEFT (877-438-4338). If you have been the victim of identity theft, see www.IdentityTheft.gov and Pub. 5027.

     Visit www.irs.gov/IdentityTheft to learn more about identity theft and how to reduce your risk.

Privacy Act Notice

Section 6109 of the Internal Revenue Code requires you to provide your correct TIN to persons (including federal agencies) who are required to file information returns with the IRS to report interest, dividends, or certain other income paid to you; mortgage interest you paid; the acquisition or abandonment of secured property; the cancellation of debt; or contributions you made to an IRA, Archer MSA, or HSA. The person collecting this form uses the information on the form to file information returns with the IRS, reporting the above information. Routine uses of this information include giving it to the Department of Justice for civil and criminal litigation and to cities, states, the District of Columbia, and U.S. commonwealths and possessions for use in administering their laws. The information also may be disclosed to other countries under a treaty, to federal and state agencies to enforce civil and criminal laws, or to federal law enforcement and intelligence agencies to combat terrorism. You must provide your TIN whether or not you are required to file a tax return. Under section 3406, payers must generally withhold a percentage of taxable interest, dividend, and certain other payments to a payee who does not give a TIN to the payer. Certain penalties may also apply for providing false or fraudulent information.

The Depositary for the Offer is:

LOGO

By Mail:
Computershare
c/o Voluntary Corporate Actions
P.O. Box 43011
Providence, RI 02940-3011

   By Overnight Courier:
Computershare
c/o Voluntary Corporate Actions
150 Royall Street
Suite V
Canton, MA 02021

        The Information Agent may be contacted at its address and telephone number listed below for questions and/or requests for additional copies of the Offer to Purchase, this Letter of Transmittal, the Notice of Guaranteed Delivery and other tender offer materials. You may also contact your broker, dealer, commercial bank, trust company or other nominee for assistance. Such copies will be furnished promptly at Purchaser's expense.

The Information Agent for the Offer is:

LOGO

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, NY 10022

Banks and Brokerage Firms Call: (212) 750-5833
Stockholders Call Toll Free: (888) 750-5834

​

Voluntary Corporate Action: COY GILD



QuickLinks

The Depositary for the Offer is
NOTE: SIGNATURES MUST BE PROVIDED BELOW. PLEASE READ ACCOMPANYING INSTRUCTIONS CAREFULLY
INSTRUCTIONS FORMING PART OF THE TERMS AND CONDITIONS OF THE OFFER

QuickLinks -- Click here to rapidly navigate through this document

Exhibit (a)(1)(C)

NOTICE OF GUARANTEED DELIVERY
For Tender of Shares of Common Stock
of
FORTY SEVEN, INC.
a Delaware corporation
at
$95.50 NET PER SHARE
Pursuant to the Offer to Purchase dated March 10, 2020
by
TORO MERGER SUB, INC.
a wholly owned subsidiary of
GILEAD SCIENCES, INC.

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT ONE MINUTE AFTER
11:59 P.M., EASTERN TIME, ON APRIL 6, 2020,
UNLESS THE OFFER IS EXTENDED OR EARLIER TERMINATED.

        This Notice of Guaranteed Delivery, or one substantially in the form hereof, must be used to accept the Offer (as defined below) if (i) certificates representing shares of common stock, par value $0.0001 per share (the "Shares"), of Forty Seven, Inc., a Delaware corporation ("Forty Seven"), are not immediately available, (ii) the procedure for book-entry transfer cannot be completed prior to the expiration of the Offer or (iii) time will not permit all required documents to reach Computershare Trust Company, N.A. (the "Depositary") prior to the expiration of the Offer. This Notice of Guaranteed Delivery may be delivered by overnight courier or mailed to the Depositary. See Section 3 of the Offer to Purchase (as defined below).

The Depositary for the Offer is:

LOGO

By Mail:
Computershare
c/o Voluntary Corporate Actions
P.O. Box 43011
Providence, RI 02940-3011		   By Overnight Courier:
Computershare
c/o Voluntary Corporate Actions
150 Royall Street, Suite V
Canton, MA 02021

FACSIMILE: (617) 360-6810
CONFIRM: (781) 575-2332

        The above number is for confirmation of facsimiles only. Do NOT call this number for questions on the Offer. All questions on the Offer should be directed to the Information Agent listed in the Offer to Purchase.

        DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY TO AN ADDRESS OTHER THAN AS SET FORTH ABOVE WILL NOT CONSTITUTE A VALID DELIVERY.

        THIS NOTICE OF GUARANTEED DELIVERY IS NOT TO BE USED TO GUARANTEE SIGNATURES. IF A SIGNATURE ON A LETTER OF TRANSMITTAL IS REQUIRED TO BE GUARANTEED BY AN ELIGIBLE INSTITUTION (AS DEFINED IN SECTION 3 OF THE OFFER TO PURCHASE) UNDER THE INSTRUCTIONS THERETO, SUCH SIGNATURE GUARANTEE MUST APPEAR IN THE APPLICABLE SPACE PROVIDED IN THE SIGNATURE BOX ON THE APPROPRIATE LETTER OF TRANSMITTAL.

        The Eligible Institution that completes this Notice of Guaranteed Delivery must communicate the guarantee to the Depositary and must deliver the Letter of Transmittal (as defined below) or an Agent's Message (as defined in Section 3 of the Offer to Purchase) and certificates for Shares (or Book-Entry Confirmation, as defined in Section 3 of the Offer to Purchase) to the Depositary within the time period shown herein. Failure to do so could result in a financial loss to such Eligible Institution.

Ladies and Gentlemen:

        The undersigned hereby tenders to Toro Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Gilead Sciences, Inc., a Delaware corporation, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated March 10, 2020 (as it may be amended or supplemented from time to time, the "Offer to Purchase"), and the related Letter of Transmittal (as it may be amended or supplemented from time to time, the "Letter of Transmittal" and, together with the Offer to Purchase, the "Offer"), receipt of which is hereby acknowledged, the number of Shares specified below, pursuant to the guaranteed delivery procedure set forth in Section 3 of the Offer to Purchase. Shares tendered by the Notice of Guaranteed Delivery will be excluded from the calculation of the Minimum Tender Condition (as defined in the Offer to Purchase), unless such Shares and other required documents are received by the Depositary by the expiration date of the Offer.

Number of Shares and Certificate No.(s):
(if available)





o    Check here if Shares will be tendered by book-entry transfer.

Name of Tendering Institution:
 


DTC Account Number:
 


Dated:
 


Name(s) of Record Holder(s):
 
 




(Please type or print)

Address(es):
 

(Zip Code)

Area Code and Tel. No.:
 

(Daytime telephone number)

Signature(s):
 


Notice of Guaranteed Delivery


GUARANTEE
(Not to be used for signature guarantee)

        The undersigned, an Eligible Institution, hereby (i) represents that the tender of Shares effected hereby complies with Rule 14e-4 under the Securities Exchange Act of 1934, as amended, and (ii) within two NASDAQ Global Select Market trading days after the date hereof, (A) guarantees delivery to the Depositary, at one of its addresses set forth above, of certificates representing the Shares tendered hereby, in proper form for transfer, together with a properly completed and duly executed Letter of Transmittal and any other documents required by the Letter of Transmittal or (B) guarantees a Book-Entry Confirmation of the Shares tendered hereby into the Depositary's account at The Depository Trust Company (pursuant to the procedures set forth in Section 3 of the Offer to Purchase), together with a properly completed and duly executed Letter of Transmittal, or an Agent's Message (defined in Section 3 of the Offer to Purchase) in lieu of such Letter of Transmittal, and any other documents required by the Letter of Transmittal.

Name of Firm:  

Address:
 
 

 
 
(Zip Code)

Area Code and Telephone No.:
 
 

(Authorized Signature)

Name:
 
(Please type or print)

Title:
 
 

Date:
 
 
NOTE:
DO NOT SEND CERTIFICATES REPRESENTING TENDERED SHARES WITH THIS NOTICE. CERTIFICATES REPRESENTING TENDERED SHARES SHOULD BE SENT WITH YOUR LETTER OF TRANSMITTAL.



QuickLinks

Notice of Guaranteed Delivery
GUARANTEE (Not to be used for signature guarantee)

Exhibit (a)(1)(D)

Offer To Purchase For Cash
All Outstanding Shares of Common Stock
of
FORTY SEVEN, INC.
a Delaware corporation
at
$95.50 NET PER SHARE
Pursuant to the Offer to Purchase dated March 10, 2020
by
TORO MERGER SUB, INC.
a wholly owned subsidiary of
GILEAD SCIENCES, INC.

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT ONE MINUTE AFTER
11:59 P.M., EASTERN TIME, ON APRIL 6, 2020,
UNLESS THE OFFER IS EXTENDED OR EARLIER TERMINATED.

March 10, 2020

To Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees:

        We have been engaged by Toro Merger Sub, Inc., a Delaware corporation ("Purchaser") and a wholly owned subsidiary of Gilead Sciences, Inc., a Delaware corporation ("Parent"), to act as Information Agent in connection with Purchaser's Offer to Purchase, dated March 10, 2020 (the "Offer to Purchase") subject to certain conditions, including the satisfaction of the Minimum Tender Condition, as defined in the Offer to Purchase, any and all of the outstanding shares of common stock, par value $0.0001 per share (the "Shares"), of Forty Seven, Inc., a Delaware corporation ("Forty Seven"), at a price of $95.50 per Share, net to the holder in cash, without interest (the "Offer Price") and subject to any withholding of taxes, upon the terms and subject to the conditions set forth in the Offer to Purchase, and the related Letter of Transmittal (the "Letter of Transmittal" and which, together with the Offer to Purchase, each as may be amended or supplemented from time to time, constitute the "Offer") enclosed herewith. Please furnish copies of the enclosed materials to those of your clients for whom you hold Shares registered in your name or in the name of your nominee.

        THE BOARD OF DIRECTORS OF FORTY SEVEN HAS UNANIMOUSLY RECOMMENDED THAT STOCKHOLDERS TENDER ALL OF THEIR SHARES TO PURCHASER PURSUANT TO THE OFFER.

        The Offer is not subject to any financing condition. The conditions to the Offer are described in Section 13 of the Offer to Purchase.

        For your information and for forwarding to your clients for whom you hold Shares registered in your name or in the name of your nominee, we are enclosing the following documents:

        We urge you to contact your clients as promptly as possible. Please note that the Offer and withdrawal rights will expire at one minute after 11:59 p.m., Eastern Time, on April 6, 2020, unless the Offer is extended or earlier terminated.

        The Offer is being made in connection with the Agreement and Plan of Merger, dated as of March 1, 2020 (together with any amendments or supplements thereto, the "Merger Agreement"), among Forty Seven, Parent and Purchaser, pursuant to which, after the completion of the Offer and the satisfaction or waiver of certain conditions, Purchaser will be merged with and into Forty Seven, without a meeting of Forty Seven's stockholders in accordance with Section 251(h) of the General Corporation Law of the State of Delaware (the "DGCL"), and Forty Seven will be the surviving corporation and a wholly owned subsidiary of Parent (such merger, the "Merger"). At the effective time of the Merger, all then outstanding Shares (other than (i) Shares held by Forty Seven (or held in Forty Seven's treasury), (ii) Shares held by Parent, Purchaser or any other direct or indirect wholly owned subsidiary of Parent and (iii) Shares held by stockholders immediately prior to the effective time of the Merger who have properly exercised and perfected their demands for appraisal of such Shares in accordance with the DGCL and have neither effectively withdrawn nor lost such rights to appraisal and payment) will be converted into the right to receive consideration equal to the Offer Price, without interest and subject to any withholding of taxes, upon the terms and subject to the conditions set forth in the Offer to Purchase.

        THE BOARD OF DIRECTORS OF FORTY SEVEN HAS UNANIMOUSLY RECOMMENDED THAT STOCKHOLDERS TENDER ALL OF THEIR SHARES TO PURCHASER PURSUANT TO THE OFFER.

        For Shares to be properly tendered pursuant to the Offer, (a) the share certificates or confirmation of receipt of such Shares under the procedure for book-entry transfer, together with a properly completed and duly executed Letter of Transmittal, including any required signature guarantees, or, in the case of book-entry transfer, either such Letter of Transmittal or an Agent's Message (as defined in Section 3 of the Offer to Purchase) in lieu of such Letter of Transmittal, and any other documents required in the Letter of Transmittal, must be timely received by the Depositary, or (b) the tendering stockholder must comply with the guaranteed delivery procedures, all in accordance with the Offer to Purchase and the Letter of Transmittal. You may gain some additional time by making use of the Notice of Guaranteed Delivery. Shares tendered by the Notice of Guaranteed Delivery will be excluded from the calculation of the Minimum Tender Condition, unless such Shares and other required documents are received by the Depositary by the Expiration Date (as defined in Section 1 of the Offer to Purchase).

        Except as set forth in the Offer to Purchase, Purchaser will not pay any fees or commissions to any broker or dealer or other person, other than to us, as the information agent, and Computershare Trust Company, N.A., as the depositary, for soliciting tenders of Shares pursuant to the Offer. Purchaser will, however, upon request, reimburse brokers, dealers, commercial banks, trust companies and other nominees for customary mailing and handling expenses incurred by them in forwarding the offering material to their customers. Purchaser will pay all stock transfer taxes applicable to its purchase of Shares pursuant to the Offer, subject to Instruction 6 of the Letter of Transmittal.

        Any inquiries you may have with respect to the Offer should be addressed to, and additional copies of the enclosed materials may be obtained from, the undersigned at the address and telephone numbers set forth below.

        Very truly yours,

        Innisfree M&A Incorporated

        Nothing contained herein or in the enclosed documents shall render you the agent of Parent, Purchaser, the Information Agent or the Depositary or any affiliate of any of them or authorize you or any other person to use any document or make any statement on behalf of any of them in connection with the Offer other than the enclosed documents and the statements contained therein.

The Information Agent for the Offer is:

LOGO

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, NY 10022

Banks and Brokerage Firms Call: (212) 750-5833
Stockholders Call Toll Free: (888) 750-5834



QuickLinks -- Click here to rapidly navigate through this document


Exhibit (a)(1)(E)

        Offer To Purchase For Cash
All Outstanding Shares of Common Stock
of
FORTY SEVEN, INC.
a Delaware corporation
at
$95.50 NET PER SHARE
Pursuant to the Offer to Purchase dated March 10, 2020
by
TORO MERGER SUB, INC.
a wholly owned subsidiary of
GILEAD SCIENCES, INC.

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT ONE MINUTE
AFTER 11:59 P.M., EASTERN TIME, ON APRIL 6, 2020,
UNLESS THE OFFER IS EXTENDED OR EARLIER TERMINATED.

March 10, 2020

To Our Clients:

        Enclosed for your consideration are the Offer to Purchase, dated March 10, 2020 (the "Offer to Purchase"), and the related Letter of Transmittal (the "Letter of Transmittal" and which, together with the Offer to Purchase, as each may be amended or supplemented from time to time, constitute, the "Offer") in connection with the offer by Toro Merger Sub, Inc., a Delaware corporation ("Purchaser") and a wholly owned subsidiary of Gilead Sciences, Inc., a Delaware corporation ("Parent"), to purchase, subject to certain conditions, including the satisfaction of the Minimum Tender Condition, as defined in the Offer to Purchase, any and all of the outstanding shares of common stock, par value $0.0001 per share (the "Shares"), of Forty Seven, Inc., a Delaware corporation ("Forty Seven"), at a price of $95.50 per Share, net to the holder in cash, without interest (the "Offer Price") and subject to any withholding of taxes, upon the terms and subject to the conditions of the Offer.

        THE BOARD OF DIRECTORS OF FORTY SEVEN HAS UNANIMOUSLY RECOMMENDED THAT YOU TENDER ALL OF YOUR SHARES PURSUANT TO THE OFFER.

        We or our nominees are the holder of record of Shares held for your account. A tender of such Shares can be made only by us as the holder of record and pursuant to your instructions. The Letter of Transmittal accompanying this letter is furnished to you for your information only and cannot be used by you to tender Shares held by us for your account.

        We request instructions as to whether you wish us to tender any or all of the Shares held by us for your account, upon the terms and subject to the conditions set forth in the enclosed Offer to Purchase and the Letter of Transmittal.

        Please note carefully the following:

        If you wish to have us tender any or all of your Shares, then please so instruct us by completing, executing, detaching and returning to us the Instruction Form on the detachable part hereof. An envelope to return your instructions to us is enclosed. If you authorize tender of your Shares, then all such Shares will be tendered unless otherwise specified on the Instruction Form.

        Your prompt action is requested. Your Instruction Form should be forwarded to us in ample time to permit us to submit the tender on your behalf before the Expiration Date.

        The Offer is being made to all holders of Shares. Purchaser is not aware of any jurisdiction in which the making of the Offer or the acceptance thereof would be prohibited by securities, "blue sky" or other valid laws of such jurisdiction. If Purchaser becomes aware of any U.S. state in which the making of the Offer or the acceptance of Shares pursuant thereto would not be in compliance with an administrative or judicial action taken pursuant to a U.S. state statute, Purchaser will make a good faith effort to comply with any such law. If, after such good faith effort, Purchaser cannot comply with any such law, the Offer will not be made to (nor will tenders be accepted from or on behalf of) the holders of Shares in such state. In any jurisdictions where applicable laws require the Offer to be made by a licensed broker or dealer, the Offer shall be deemed to be made on behalf of Purchaser by one or more registered brokers or dealers licensed under the laws of such jurisdiction to be designated by Purchaser.

INSTRUCTION FORM
With Respect to the Offer to Purchase for Cash
All Outstanding Shares of Common Stock
of
FORTY SEVEN, INC.
a Delaware corporation
at
$95.50 NET PER SHARE
Pursuant to the Offer to Purchase dated March 10, 2020
by
TORO MERGER SUB, INC.
a wholly owned subsidiary of
GILEAD SCIENCES, INC.

        The undersigned acknowledge(s) receipt of your letter and the enclosed Offer to Purchase, dated March 10, 2020 ("Offer to Purchase"), and the related Letter of Transmittal ("Letter of Transmittal" and which, together with the Offer to Purchase, each as may be amended or supplemented from time to time, constitute, the "Offer"), in connection with the offer by Toro Merger Sub, Inc., a Delaware corporation ("Purchaser") and a wholly owned subsidiary of Gilead Sciences, Inc., a Delaware corporation, to purchase, subject to certain conditions, including the satisfaction of the Minimum Tender Condition, as defined in the Offer to Purchase, any and all of the outstanding shares of common stock, par value $0.0001 per share (the "Shares"), of Forty Seven, Inc., a Delaware corporation, at a price of $95.50 per Share, net to the holder in cash, without interest and subject to any withholding of taxes, upon the terms and subject to the conditions of the Offer.

        The undersigned hereby instruct(s) you to tender to Purchaser the number of Shares indicated below or, if no number is indicated, all Shares held by you for the account of the undersigned, upon the terms and subject to the conditions set forth in the Offer. The undersigned understands and acknowledges that all questions as to validity, form and eligibility of the surrender of any certificate representing Shares submitted on my behalf will be determined by Purchaser and such determination shall be final and binding.

ACCOUNT NUMBER: ​                                                                                                                           

NUMBER OF SHARES BEING TENDERED HEREBY:            SHARES*

        The method of delivery of this document is at the election and risk of the tendering stockholder. If delivery is by mail, then registered mail with return receipt requested, properly insured, is recommended. In all cases, sufficient time should be allowed to ensure timely delivery by the Expiration Date (as defined in the Offer to Purchase).

Dated:    
 		      
Signature(s)

 
 
 
 

Please Print Name(s)

 

Address:  
(Include Zip Code)

 

Area code and Telephone no.  

 

Tax Identification or Social Security No.  
*
Unless otherwise indicated, it will be assumed that all Shares held by us for your account are to be tendered.



QuickLinks


Exhibit (a)(1)(F)

 

This announcement is neither an offer to purchase nor a solicitation of an offer to sell Shares (as defined below). The Offer (as defined below) is made solely pursuant to the Offer to Purchase, dated March 10, 2020, and the related Letter of Transmittal, and any amendments or supplements to such Offer to Purchase or Letter of Transmittal. Purchaser (as defined below) is not aware of any state where the making of the Offer is prohibited by any administrative or judicial action pursuant to any valid state statute. If Purchaser becomes aware of any valid state statute prohibiting the making of the Offer or the acceptance of the Shares pursuant thereto, Purchaser will make a good faith effort to comply with that state statute or seek to have such statute declared inapplicable to the Offer. If, after a good faith effort, Purchaser cannot do so, Purchaser will not make the Offer to, nor will tenders be accepted from or on behalf of, the holders of Shares in that state. Except as set forth above, the Offer is being made to all holders of Shares. In any jurisdiction where the securities, “blue sky” or other laws require the Offer to be made by a licensed broker or dealer, the Offer will be deemed to be made on behalf of Purchaser by one or more registered brokers or dealers that are licensed under the laws of such jurisdiction.

 

Notice of Offer to Purchase

All Outstanding Shares of Common Stock

of

Forty Seven, Inc.

at

$95.50 Net Per Share

Pursuant to the Offer to Purchase dated March 10, 2020

by

Toro Merger Sub, Inc.

a wholly owned subsidiary of

Gilead Sciences, Inc.

 

Toro Merger Sub, Inc., a Delaware corporation (“Purchaser”), is offering to purchase all outstanding shares of common stock, par value $0.0001 per share (the “Shares”), of Forty Seven, Inc., a Delaware corporation (“Forty Seven”), at a price per Share of $95.50, net to the holder in cash, without interest (the “Offer Price”) and subject to any withholding of taxes, upon the terms and subject to the conditions described in the Offer to Purchase, dated March 10, 2020 (together with any amendments or supplements thereto, the “Offer to Purchase”), and in the related Letter of Transmittal (together with any amendments or supplements thereto, the “Letter of Transmittal” and, together with the Offer to Purchase, the “Offer”). Purchaser is a wholly owned subsidiary of Gilead Sciences, Inc., a Delaware corporation (“Gilead”).

 

The Offer is being made in connection with the Agreement and Plan of Merger, dated as of March 1, 2020 (together with any amendments or supplements thereto, the “Merger Agreement”), among Forty Seven, Gilead and Purchaser, pursuant to which, after the completion of the Offer and the satisfaction or waiver of certain conditions, Purchaser will be merged with and into Forty Seven, and Forty Seven will be the surviving corporation and a wholly owned subsidiary of Gilead (such merger, the “Merger”). At the effective time of the Merger, each Share issued and then outstanding (other than (i) Shares held by Forty Seven (or held in Forty Seven’s treasury), (ii) Shares held by Gilead, Purchaser or any other direct or indirect wholly owned subsidiary of Gilead and (iii) Shares held by stockholders immediately prior to the effective time of the Merger who have properly exercised and perfected their demands for appraisal of such Shares in accordance with the General Corporation Law of the State of Delaware (“DGCL”) and have neither effectively withdrawn nor lost such rights to appraisal and payment) will be canceled and converted automatically into the right to receive the Offer Price. As a result of the Merger, Forty Seven will cease to be a publicly-traded company and will become wholly owned by Gilead. Under no circumstances will interest be paid on the purchase price for Shares, regardless of any extension of the Offer or any delay in making payment for Shares. The parties to the Merger Agreement have agreed that, upon the terms and subject to the conditions specified in the Merger Agreement, the Merger will become effective as soon as practicable after the consummation of the Offer, without a meeting of Forty Seven’s stockholders to adopt the Merger Agreement, in accordance with Section 251(h) of the DGCL. Accordingly, if the Offer is consummated, Purchaser does not anticipate seeking the approval of Forty Seven’s remaining public stockholders before effecting the Merger. The Merger Agreement is more fully described in the Offer to Purchase.

 

Tendering stockholders who have Shares registered in their names and who tender directly to Computershare Trust Company, N.A. (the “Depositary”) will not be obligated to pay brokerage fees or commissions or, except as set forth in the Letter of Transmittal, transfer taxes on the purchase of Shares by Purchaser pursuant to the Offer. Stockholders who hold their Shares through a broker or bank should consult with such institution as to whether it charges any service fees or commissions.

 

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT ONE MINUTE AFTER 11:59 P.M., EASTERN TIME, ON APRIL 6, 2020 (SUCH DATE, OR ANY SUBSEQUENT DATE TO WHICH THE EXPIRATION OF THE OFFER IS EXTENDED, THE “EXPIRATION DATE”), UNLESS THE OFFER IS EXTENDED OR EARLIER TERMINATED.

 

The Offer is conditioned upon, among other things, (a) the Merger Agreement not having been terminated in accordance with its terms (the “Termination Condition”) and (b) the satisfaction of:

 

(i)       the Minimum Tender Condition (as described below);

(ii)      the HSR Condition (as described below); and

(iii)     the Governmental Impediment Condition (as described below).

 

     The Offer is not subject to a financing condition. The Minimum Tender Condition requires that the number of Shares validly tendered and not validly withdrawn, together with any Shares then beneficially owned by Gilead and its subsidiaries, equals one Share more than 50% of the sum of (i) the total number of Shares outstanding at the time of the expiration of the Offer, plus (ii) the total number of Shares that Forty Seven would be required to issue upon conversion, settlement, exchange or exercise of all options, warrants, rights or securities vested and outstanding at the time of the expiration of the Offer that are convertible, exchangeable or exercisable into Shares (whether then outstanding or for which the conversion, settlement, exchange or exercise date has already occurred, but in any event without duplication) (excluding Shares tendered in the Offer pursuant to guaranteed delivery procedures that have not yet been “received” (as such term is defined in Section 251(h)(6)(f) of the DGCL)). The HSR Condition requires that the waiting period (or any extension thereof) applicable to the Offer under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, and the rules and regulations promulgated thereunder, shall have expired or otherwise been terminated. The Governmental Impediment Condition requires that there be no judgment, temporary restraining order, preliminary or permanent injunction or other order, decree or ruling restraining, enjoining or otherwise preventing the acquisition of or payment for Shares pursuant to the Offer or the consummation of the Offer or the Merger in any jurisdiction in which Gilead or Forty Seven have material business operations or law or other legal prohibition by any governmental body in any jurisdiction in which Gilead or Forty Seven have material business operations in effect which prohibits or makes illegal the acquisition of or payment for Shares pursuant to the Offer or the consummation of the Merger. The Offer is also subject to other conditions as described in the Offer to Purchase (collectively, the “Offer Conditions”). See Section 13—“Conditions of the Offer” of the Offer to Purchase.

 

 

After careful consideration, the Forty Seven board of directors has, subject to the terms and upon the conditions set forth in the Merger Agreement, unanimously: (i) determined that the Merger Agreement and the transactions contemplated thereby, including the Offer and the Merger, are fair to, and in the best interest of, Forty Seven and its stockholders, (ii) declared it advisable to enter into the Merger Agreement, (iii) approved the execution, delivery and performance by Forty Seven of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Offer and the Merger, (iv) resolved that the Merger shall be effected under Section 251(h) of the DGCL, and (v) resolved to recommend that the stockholders of Forty Seven accept the Offer and tender their Shares to Purchaser pursuant to the Offer.

 

The Merger Agreement contains provisions to govern the circumstances in which Purchaser is required to extend the Offer and in which Gilead is required to cause Purchaser to extend the Offer. Specifically, the Merger Agreement provides that Purchaser shall (and Gilead shall cause Purchaser to) extend the Offer (i) if, as of the then-scheduled Expiration Date, any Offer Condition is not satisfied (unless such condition is waivable by Purchaser or Gilead and has been waived), for additional periods of up to 10 business days per extension to permit such Offer Condition to be satisfied; and (ii) from time to time for any period required by any legal requirement, any interpretation or position of the SEC or its staff or the NASDAQ Global Select Market applicable to the Offer. Notwithstanding the foregoing, in no event will Purchaser be required to extend the Offer beyond June 1, 2020 (such date, including as it may be extended pursuant to the terms of the Merger Agreement, the “End Date”) or the earlier termination of the Merger Agreement, and in no event will Purchaser be permitted to extend the Offer beyond the End Date or the earlier termination of the Merger Agreement without Forty Seven’s prior written consent.

 

The purpose of the Offer and the Merger is for Gilead and its affiliates, through Purchaser, to acquire control of, and the entire equity interest in, Forty Seven. Following the consummation of the Offer, subject to the satisfaction or waiver of the conditions set forth in the Merger Agreement, Gilead and Purchaser intend to effect the Merger. No appraisal rights are available to holders of Shares in connection with the Offer. However, if the Merger is consummated, a stockholder of Forty Seven that has not tendered its Shares in the Offer will have rights under Section 262 of the DGCL to dissent from the Merger and demand appraisal of, and obtain payment in cash for the “fair value” of, that stockholder’s Shares.

 

On the terms and subject to the conditions of the Merger Agreement and the applicable rules and regulations of the SEC, Purchaser expressly reserves the right to (i) increase the amount of cash constituting the Offer Price, (ii) waive any Offer Condition (to the extent permitted under applicable Legal Requirements (as defined in the Merger Agreement)) and (iii) make any other changes in the terms and conditions of the Offer that are not inconsistent with the Merger Agreement. However, without the consent of Forty Seven, Gilead and Purchaser are not permitted to (i) decrease the Offer Price, (ii) change the form of consideration payable in the Offer (provided that nothing in the Merger Agreement shall limit the ability of Gilead and Purchaser to increase the cash consideration payable in the Offer), (iii) decrease the maximum number of Shares sought to be purchased in the Offer, (iv) impose conditions or requirements to the Offer in addition to the Offer Conditions, (v) amend, modify or waive the Minimum Tender Condition, the Termination Condition, the HSR Condition or the Governmental Impediment Condition, (vi) otherwise amend or modify any of the other terms of the Offer in a manner that adversely affects, or would reasonably be expected to adversely affect, any holder of Shares in its capacity as such, (vii) terminate the Offer or accelerate, extend or otherwise change the Expiration Date except as provided in the Merger Agreement, or (viii) provide any “subsequent offering period” (or any extension thereof) within the meaning of applicable SEC rules and regulations.

 

Any extension, waiver or amendment of the Offer or termination of the Offer will be followed, as promptly as practicable, by public announcement thereof, such announcement in the case of an extension to be issued no later than 9:00 a.m., Eastern Time, on the next business day after the previously scheduled Expiration Date.

 

For purposes of the Offer, Purchaser will be deemed to have accepted for payment, and thereby purchased, Shares validly tendered, and not properly withdrawn, prior to the expiration of the Offer if and when Purchaser gives oral or written notice to the Depositary of Purchaser’s acceptance for payment of such Shares pursuant to the Offer. Upon the terms and subject to the conditions of the Offer, payment for Shares accepted for payment pursuant to the Offer will be made by deposit of the aggregate Offer Price for such Shares with the Depositary, which will act as paying agent for the tendering stockholders for the purpose of receiving payments from Purchaser and transmitting such payments to the tendering stockholders. Under no circumstances will interest be paid on the Offer Price for Shares, regardless of any extension of the Offer or any delay in making payment for Shares.

 

In all cases, payment for Shares tendered and accepted for payment pursuant to the Offer will be made only after timely receipt by the Depositary of (a) certificates for such Shares (“Share Certificates”) or timely confirmation of the book-entry transfer of such Shares (“Book-Entry Confirmations”) into the Depositary’s account at The Depository Trust Company (“DTC”) pursuant to the procedures set forth in the Offer to Purchase, (b) a Letter of Transmittal, properly completed and duly executed, with any required signature guarantees (or, in the case of a book-entry transfer, an Agent’s Message (as defined in the Offer to Purchase) in lieu of the Letter of Transmittal) and (c) any other documents required by the Letter of Transmittal. Accordingly, tendering stockholders may be paid at different times depending upon when Share Certificates or Book-Entry Confirmations with respect to Shares are actually received by the Depositary.

 

Shares tendered pursuant to the Offer may be withdrawn at any time prior to the expiration of the Offer and, unless theretofore accepted for payment by Purchaser pursuant to the Offer, may also be withdrawn at any time after May 9, 2020, which is the 60th day after the date of the commencement of the Offer.

 

For a withdrawal of Shares to be effective, a written or facsimile transmission notice of withdrawal must be timely received by the Depositary at its address set forth on the back cover of the Offer to Purchase. Any such notice of withdrawal must specify the name of the person having tendered the Shares to be withdrawn, the number of Shares to be withdrawn and the name of the record holder of the Shares to be withdrawn, if different from that of the person who tendered such Shares. The signature(s) on the notice of withdrawal must be guaranteed by an Eligible Institution (as defined in the Offer to Purchase), unless such Shares have been tendered for the account of any Eligible Institution. If Shares have been tendered pursuant to the procedures for book-entry transfer as set forth in the Offer to Purchase, any notice of withdrawal must specify the name and number of the account at DTC to be credited with the withdrawn Shares and must otherwise comply with DTC’s procedures. If certificates representing the Shares to be withdrawn have been delivered or otherwise identified to the Depositary, the name of the registered holder and the serial numbers shown on such certificates must also be furnished to the Depositary as aforesaid prior to the physical release of such certificates.

 

 

All questions as to the form and validity (including time of receipt) of any notice of withdrawal will be determined by Purchaser, in its sole discretion, which determination shall be final and binding, subject to the rights of tendering stockholders to challenge Purchaser’s determination in a court of competent jurisdiction. No withdrawal of tendered Shares shall be deemed to have been properly made until all defects and irregularities have been cured or waived. None of Gilead, Purchaser or any of their respective affiliates or assigns, the Depositary, the Information Agent (listed below), or any other person will be under any duty to give notification of any defects or irregularities in any notice of withdrawal or incur any liability for failure to give such notification. Withdrawals of tendered Shares may not be rescinded, and any Shares properly withdrawn will be deemed not to have been validly tendered for purposes of the Offer. However, withdrawn Shares may be retendered by following one of the procedures for tendering Shares described in the Offer to Purchase at any time prior to the expiration of the Offer.

 

The information required to be disclosed by paragraph (d)(1) of Rule 14d-6 under the Securities and Exchange Act of 1934, as amended, is contained in the Offer to Purchase and is incorporated herein by reference.

 

Forty Seven has provided Purchaser with Forty Seven’s stockholder list and securities position listings for the purpose of disseminating the holders of Shares information regarding the Offer. The Offer to Purchase and related Letter of Transmittal will be mailed to record holders of Shares whose names appear on Forty Seven’s stockholder list and will be furnished to brokers, dealers, commercial banks, trust companies and similar persons whose names, or the names of whose nominees, appear on the stockholder list or, if applicable, who are listed as participants in a clearing agency’s security position listing for subsequent transmittal to beneficial owners of Shares.

 

The receipt of the Offer Price for Shares in the Offer or consideration for Shares in the Merger will be a taxable transaction for U.S. federal income tax purposes. Stockholders should consult with their tax advisors as to the particular tax consequences of the Offer and the Merger to them. For a more complete description of the principal U.S. federal income tax consequences of the Offer and the Merger, see the Offer to Purchase.

 

The Offer to Purchase, the related Letter of Transmittal and Forty Seven’s Solicitation/Recommendation Statement on Schedule 14D-9 (which contains the recommendation of the Forty Seven board of directors and the reasons therefor) contain important information and should be read carefully and in their entirety before any decision is made with respect to the Offer.

 

Questions and requests for assistance may be directed to the Information Agent at the address and telephone numbers set forth below. Requests for copies of the Offer to Purchase and the related Letter of Transmittal, the Notice of Guaranteed Delivery and other tender offer materials may be directed to the Information Agent or to brokers, dealers, commercial banks or trust companies. Such copies will be furnished promptly at Purchaser’s expense. Except as set forth in the Offer to Purchase, neither Purchaser nor Gilead will pay any fees or commissions to any broker or dealer or any other person for soliciting tenders of Shares pursuant to the Offer.

 

The Information Agent for the Offer is:

 

 

Innisfree M&A Incorporated

501 Madison Avenue, 20th Floor

New York, New York 10022

Shareholders may call toll free: (888) 750-5834

Banks and Brokers may call collect: (212) 750-5833

 

March 10, 2020