GILEAD SCIENCES, INC.

Exhibit 10.20

NON-EMPLOYEE DIRECTOR AWARD

GILEAD SCIENCES, INC.

RESTRICTED STOCK UNIT ISSUANCE AGREEMENT

RECITALS

A. The Board has adopted the Plan for the purpose of providing incentives to attract, retain and motivate eligible Employees, Directors and Consultants who provide services to the Corporation (or any Related Entity).

B. Participant is to render valuable services to the Corporation as a non-employee Director, and this Agreement is executed pursuant to, and is intended to carry out the purposes of, the Plan in connection with the Corporation’s issuance of shares of Common Stock to Participant thereunder.

C. All capitalized terms in this Agreement shall have the meaning assigned to them in the attached Appendix A.

NOW, THEREFORE, the Corporation hereby awards Restricted Stock Units to Participant upon the following terms and conditions:

1. Grant of Restricted Stock Units. The Corporation hereby awards to Participant, as of the Award Date, Restricted Stock Units under the Plan. Each Restricted Stock Unit that vests hereunder will entitle Participant to receive one share of Common Stock on the specified issuance date for that unit. The number of shares of Common Stock subject to the awarded Restricted Stock Units, the applicable vesting schedule for those shares, the dates on which those vested shares shall become issuable to Participant and the remaining terms and conditions governing the award (the “Award”) shall be as set forth in this Agreement.

AWARD SUMMARY

2. Limited Transferability. Prior to actual receipt of the Shares which vest hereunder, Participant may not transfer any interest in the Award or the underlying Shares. Any Shares which vest hereunder but which otherwise remain unissued at the time of Participant’s death may be transferred pursuant to the provisions of Participant’s will or the laws of inheritance or to Participant’s designated beneficiary or beneficiaries of this Award. Participant may also direct the Corporation to re-issue the stock certificates for any Shares which in fact vest and become issuable under the Award during his or her lifetime to one or more designated members of Participant’s Immediate Family or a trust established for Participant and/or the members of his or her Immediate Family.

3. Cessation of Service. Except as otherwise provided in Paragraph 5 below, should Participant cease Continuous Service for any reason prior to vesting in the Shares pursuant to the Normal Vesting Schedule, then the Award will be immediately cancelled with respect to those unvested Shares, and the number of Restricted Stock Units will be reduced accordingly. Participant shall thereupon cease to have any right or entitlement to receive any Shares under those cancelled units. However, for purposes of this Agreement, Participant shall not be deemed to cease Continuous Service if Participant continues to serve the Corporation as a Director Emeritus immediately following his or her cessation of service as a Board member without an intervening break in Continuous Service.

4. Stockholder Rights and Dividend Equivalents

(a) The holder of this Award shall not have any stockholder rights, including voting, dividend or liquidation rights, with respect to the Shares subject to the Award until Participant becomes the record holder of those Shares upon their actual issuance following the Corporation’s collection of the applicable Withholding Taxes.

(b) Notwithstanding the foregoing, should any dividend or other distribution, whether regular or extraordinary and whether payable in cash, securities (other than Common Stock) or other property, be declared and paid on the outstanding Common Stock while one or more Shares remain subject to this Award (i.e., those Shares are not otherwise issued and outstanding for purposes of entitlement to the dividend or distribution), then a special book account shall be established for Participant and credited with a phantom dividend equivalent to the actual dividend or distribution which would have been paid on the Shares at the time subject to this Award had they been issued and outstanding and entitled to that dividend or distribution. As the Shares subsequently vest hereunder, the phantom dividend equivalents so credited to those Shares in the book account shall vest and shall be distributed to Participant (in the same

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form the actual dividend or distribution was paid to the holders of the Common Stock entitled to that dividend or distribution or in such other form as the Administrator deems appropriate under the circumstances) concurrently with the issuance of the vested Shares to which those phantom dividend equivalents relate.

5. Change of Control.

(a) Should Participant remain in Continuous Service until the effective date of a Change in Control, then the Restricted Stock Units at the time subject to this Award will vest immediately prior to the closing of the Change in Control. The Shares subject to those vested units shall be converted into the right to receive the same consideration per share of Common Stock payable to the other stockholders of the Corporation in consummation of that Change in Control, and such consideration per Share shall be distributed to Participant at the same time as such shareholder payments, but such distribution to Participant shall in all events be completed no later than the later of (i) the close of the calendar year in which such Change in Control is effected or (ii) the fifteenth (15th) of the third (3rd) calendar month following the effective date of that Change in Control.

(b) This Agreement shall not in any way affect the right of the Corporation to adjust, reclassify, reorganize or otherwise change its capital or business structure or to merge, consolidate, dissolve, liquidate or sell or transfer all or any part of its business or assets.

6. Adjustment in Shares. Should any change be made to the Common Stock by reason of any stock split, stock dividend, recapitalization, combination of shares, exchange of shares, spin-off transaction or other change affecting the outstanding Common Stock as a class without the Corporation’s receipt of consideration, or should the value of outstanding shares of Common Stock be substantially reduced as a result of a spin-off transaction or an extraordinary dividend or distribution, or should there occur any merger, consolidation or other reorganization, then equitable adjustments shall be made by the Administrator to the total number and/or class of securities issuable pursuant to this Award in order to reflect such change. In making such adjustments, the Administrator shall take into account any amounts to be credited to Participant’s book account under Paragraph 4(b) in connection with the transaction, and the determination of the Administrator shall be final, binding and conclusive. In the event of a Change in Control, the provisions of Paragraph 5 shall be controlling.

7. Issuance of Shares of Common Stock.

(a) On the date on which the Shares are to be issued in accordance with the express provisions of this Agreement, the Corporation shall issue to or on behalf of the Participant a certificate (which may be in electronic form) for those Shares and shall concurrently distribute to the Participant any phantom dividend equivalents with respect to those Shares, subject in each instance to the Corporation’s collection of the applicable Withholding Taxes.

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(b) Except as otherwise provided in Paragraph 5, the settlement of all Restricted Stock Units which vest under the Award shall be made solely in shares of Common Stock. In no event, however, shall any fractional shares be issued. Accordingly, the total number of shares of Common Stock to be issued at the time the Award vests shall, to the extent necessary, be rounded down to the next whole share in order to avoid the issuance of a fractional share.

8. Compliance with Laws and Regulations. The issuance of shares of Common Stock pursuant to the Award shall be subject to compliance by the Corporation and Participant with all Applicable Laws relating thereto.

9. Notices. Any notice required to be given or delivered to the Corporation under the terms of this Agreement shall be in writing and addressed to the Corporation at its principal corporate offices. Any notice required to be given or delivered to Participant shall be in writing and addressed to Participant at the most current address then indicated for Participant on the Corporation’s employee records or shall be delivered electronically to Participant through the Corporation’s electronic mail system. All notices shall be deemed effective upon personal delivery or delivery through the Corporation’s electronic mail system or upon deposit in the U.S. mail, postage prepaid and properly addressed to the party to be notified.

10. Successors and Assigns. Except to the extent otherwise provided in this Agreement, the provisions of this Agreement shall inure to the benefit of, and be binding upon, the Corporation and its successors and assigns and Participant, the legal representatives, heirs and legatees of Participant’s estate and any beneficiaries of the Award designated by Participant.

11. Construction. This Agreement and the Award evidenced hereby are made and granted pursuant to the Plan and are in all respects limited by and subject to the terms of the Plan. All decisions of the Administrator with respect to any question or issue arising under the Plan or this Agreement shall be conclusive and binding on all persons having an interest in the Award.

12. Governing Law. The interpretation, performance and enforcement of this Agreement shall be governed by the laws of the State of California without resort to that State’s conflict-of-laws rules.

13. No Impairment of Rights. This Agreement shall not in any way be construed or interpreted so as to affect adversely or otherwise impair the right of the Corporation or its stockholders to remove Participant from the Board at any time in accordance with the provisions of applicable law.

14. Plan Prospectus. The official prospectus for the Plan is attached if this Award the first restricted stock unit award made to Participant under the Plan. Participant may obtain an additional printed copy of the prospectus by contacting Stock Administration through the internet at ***@*** or by telephoning ###-###-####.

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15. Participant Acceptance. Participant must accept the terms and conditions of this Agreement either electronically through the electronic acceptance procedure established by the Corporation or through a written acceptance delivered to the Corporation in a form satisfactory to the Corporation,

IN WITNESS WHEREOF, Gilead Sciences, Inc. has caused this Agreement to be executed on its behalf by its duly-authorized officer on the day and year first indicated above.

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APPENDIX A

DEFINITIONS

The following definitions shall be in effect under the Agreement:

A. Administrator shall mean the Compensation Committee of the Board in its capacity as administrator of the Plan.

B. Agreement shall mean this Restricted Stock Unit Issuance Agreement.

C. Applicable Laws shall mean the legal requirements related to the Plan and the Award under applicable provisions of the federal securities laws, state corporate and securities laws, the Code, the rules of any applicable Stock Exchange on which the Common Stock is listed for trading, and the rules of any non-U.S. jurisdiction applicable to Awards granted to residents therein.

D. Award shall mean the award of restricted stock units made to Participant pursuant to the terms of this Agreement.

E. Award Date shall mean the date the restricted stock units are awarded to Participant pursuant to the Agreement and shall be the date indicated in Paragraph 1 of the Agreement.

F. Board shall mean the Corporation’s Board of Directors.

G. Cause shall mean the termination of Participant’s Continuous Service as a result of his or her (i) performance of any act, or failure to perform any act, in bad faith and to the detriment of the Corporation; (ii) dishonesty, intentional misconduct, material breach of any fiduciary duty owed to the Corporation; or (iii) commission of a crime involving dishonesty, breach of trust, or physical or emotional harm to any person.

H. Change in Control shall mean a change in ownership or control of the Corporation effected through the consummation of any of the following transactions:

(i) a merger, consolidation or other reorganization approved by the Corporation’s stockholders, unless securities representing more than fifty percent (50%) of the total combined voting power of the voting securities of the successor corporation are immediately thereafter beneficially owned, directly or indirectly and in substantially the same proportion, by the persons who beneficially owned the Corporation’s outstanding voting securities immediately prior to such transaction;

(ii) a sale, transfer or other disposition of all or substantially all of the Corporation’s assets;

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(iii) the closing of any transaction or series of related transactions pursuant to which any person or any group of persons comprising a “group” within the meaning of Rule 13d-5(b)(1) of the 1934 Act (other than the Corporation or a person that, prior to such transaction or series of related transactions, directly or indirectly controls, is controlled by or is under common control with, the Corporation) becomes directly or indirectly (whether as a result of a single acquisition or by reason of one or more acquisitions within the twelve (12)-month period ending with the most recent acquisition) the beneficial owner (within the meaning of Rule 13d-3 of the 1934 Act) of securities possessing (or convertible into or exercisable for securities possessing) more than fifty percent (50%) of the total combined voting power of the Corporation’s outstanding securities (as measured in terms of the power to vote with respect to the election of Board members) outstanding immediately after the consummation of such transaction or series of related transactions, whether such transaction involves a direct issuance from the Corporation or the acquisition of outstanding securities held by one or more of the Corporation’s existing stockholders; or

(iv) a change in the composition of the Board over a period of twelve (12) consecutive months or less such that a majority of the Board members ceases, by reason of one or more contested elections for Board membership, to be comprised of individuals who either (A) have been Board members continuously since the beginning of such period or (B) have been elected or nominated for election as Board members during such period by at least a majority of the Board members described in clause (A) who were still in office at the time the Board approved such election or nomination.

In no event, however, shall a Change in Control be deemed to occur upon a merger, consolidation or other reorganization effected primarily to change the State of the Corporation’s incorporation or to create a holding company structure pursuant to which the Corporation becomes a wholly-owned subsidiary of an entity whose outstanding voting securities immediately after its formation are beneficially owned, directly or indirectly and in substantially the same proportion, by the persons who beneficially owned the Corporation’s outstanding voting securities immediately prior to the formation of such entity.

F. Code shall mean the Internal Revenue Code of 1986, as amended.

G. Common Stock shall mean shares of the Corporation’s common stock.

H. Consultant shall mean any person, including an advisor, who is compensated by the Corporation or any Related Entity for services performed as a non-employee consultant; provided, however, that the term “Consultant” shall not include non-employee Directors serving in their capacity as Board members. The term “Consultant” shall include (i) a former Board member during his or her period of service as Director Emeritus immediately following his or her cessation of service as a Board member, without an intervening break in Continuous Service, or (ii) an individual serving as a member of the board of directors of a Related Entity.

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I. Continuous Service shall mean the performance of services for the Corporation or a Related Entity (whether now existing or subsequently established) by a person in the capacity of an Employee, Director or Consultant. For purposes of this Agreement, Participant shall be deemed to cease Continuous Service immediately upon the occurrence of either of the following events: (i) Participant no longer performs services in any of the foregoing capacities for the Corporation or any Related Entity or (ii) the entity for which Participant is performing such services ceases to remain a Related Entity of the Corporation, even though Participant may subsequently continue to perform services for that entity.

J. Corporation shall mean Gilead Sciences, Inc., a Delaware corporation, and any successor corporation to all or substantially all of the assets or voting stock of Gilead Sciences, Inc. which shall by appropriate action adopt the Plan.

K. Director shall mean a member of the Board.

L. Domestic Partner shall mean a person who meets and continues to meet all of the criteria detailed in the Gilead Sciences Affidavit of Domestic Partnership when the Domestic Partnership has been internally registered with the Corporation by filing with the Corporation an original, properly completed, notarized Gilead Sciences Affidavit of Domestic Partnership.

M. Employee shall mean any person who is in the employ of the Corporation (or any Related Entity), subject to the control and direction of the Corporation or Related Entity as to both the work to be performed and the manner and method of performance.

N. Fair Market Value per share of Common Stock on any relevant date shall be the closing price per share of Common Stock (or the closing bid, if no sales were reported) on that date, as quoted on the Stock Exchange that is at the time serving as the primary trading market for the Common Stock; provided, however, that if there no reported closing price or closing bid for that date, then the closing price or closing bid, as applicable, for the last trading date on which such closing price or closing bid was quoted shall be determinative of such Fair Market Value. The applicable quoted price shall be as reported in The Wall Street Journal or such other source as the Administrator deems reliable.

O. Immediate Family shall mean, with respect to Participant, any child, stepchild, grandchild, parent, stepparent, grandparent, spouse, former spouse, sibling, niece, nephew, mother-in-law, father-in-law, son-in-law, daughter-in-law, brother-in-law or sister-in-law including adoptive relationships, Domestic Partner, a trust in which such persons (or person) have more than fifty percent (50%) of the beneficial interest, a foundation in which such persons (or person) control the management of the entity’s assets, or any other entity in which such persons (or person) own more than fifty percent (50%) of the voting interests.

P. 1934 Act shall mean the Securities Exchange Act of 1934, as amended from time to time.

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Q. Normal Vesting Schedule shall mean the schedule set forth in Paragraph 1 of the Agreement, pursuant to which the Restricted Stock Units and the underlying Shares are to vest upon Participant’s completion of one year of Continuous Service measured from the Award Date.

R. Participant shall mean the person to whom the Award is made pursuant to the Agreement.

S. Parent shall mean a “parent corporation,” whether now existing or hereafter established, as defined in Section 424(e) of the Code.

T. Plan shall mean the Corporation’s 2004 Equity Incentive Plan, as amended and restated from time to time.

U. Related Entity shall mean (i) any Parent or Subsidiary of the Corporation and (ii) any corporation in an unbroken chain of corporations beginning with the Corporation and ending with the corporation in the chain for which Participant provides services as an Employee, Director or Consultant, provided each corporation in such chain owns securities representing at least twenty percent (20%) of the total outstanding voting power of the outstanding securities of another corporation or entity in such chain and there is a legitimate non-tax business purpose for making this Award to Participant.

V. Stock Exchange shall mean the American Stock Exchange, the Nasdaq Global or Global Select Market or the New York Stock Exchange.

W. Subsidiary shall mean a “subsidiary corporation,” whether now existing or hereafter established, as defined in Section 424(f) of the Code.

X. Withholding Taxes shall mean the federal, state and local taxes required to be withheld by the Corporation in connection with the issuance of the shares of Common Stock which vest under the Award and any phantom dividend equivalents distributed with respect to those shares.

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