GILEAD SCIENCES, INC. 2005 DEFERRED COMPENSATION PLAN AS AMENDED AND RESTATED OCTOBER 22, 2007 AND SUBSEQUENTLY AMENDED EFFECTIVE JANUARY 1, 2008 AND OCTOBER 23, 2008 TABLE OF CONTENTS

Exhibit 10.26

GILEAD SCIENCES, INC.

2005 DEFERRED COMPENSATION PLAN

AS AMENDED AND RESTATED OCTOBER 22, 2007

AND SUBSEQUENTLY AMENDED EFFECTIVE JANUARY 1, 2008

AND OCTOBER 23, 2008

TABLE OF CONTENTS

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1.1 Successor Plan. The Plan is the successor plan to the Gilead Sciences, Inc. Deferred Compensation Plan, effective January 1, 2002, as amended (the “Prior Plan”). Effective as of December 31, 2004, the Prior Plan was frozen, and no new contributions were permitted to be made to it; provided, however, that any deferrals made under the Prior Plan before January 1, 2005 will continue to be governed by the terms and conditions of the Prior Plan as in effect on December 31, 2004. Any deferrals made under the Prior Plan after December 31, 2004 will be deemed to have been made under this Plan, and all such deferrals will accordingly be governed by the terms and conditions of this Plan, as it may be amended from time to time.

1.2 Restatement. The purpose of the October 22, 2007 restatement, as subsequently amended effective January 1, 2008, is to evidence the documentary compliance of the Plan, effective retroactive to January 1, 2005, with the applicable requirements of Section 409A of the Internal Revenue Code, the Treasury Regulations issued under Section 409A and the interim guidance provided by the Internal Revenue and the Treasury Department prior to the publication of the final Section 409A Regulations. The Plan as so restated was further amended on October 23, 2008 in order to allow commissions to be deferred and to effect certain clarifications to the distribution provisions.

2.1 Plan Purpose. The Employer maintains the Plan, a deferred compensation plan, for the benefit of (i) a select group of management and other highly compensated employees of the Employer and (ii) the non-employee members of the Employer’s Board of Directors. Each other Participating Employer will also maintain the Plan as a deferred compensation plan for the benefit of a select group of its management personnel and other highly compensated employees. The Participating Employers intend that the existence of the Trust will not alter the characterization of the Plan as “unfunded” for purposes of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), and will not be deemed to provide income to Participants under the Plan prior to the actual payment of their vested accrued benefits hereunder. The Participating Employers intend that the Plan comply with the requirements of Section 409A of the Code and the regulations promulgated thereunder.

3.1 Effective Date. The effective date of the Plan is January 1, 2005, except as otherwise noted herein.

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4.1 Definitions.

(a) Wherever used herein, the following terms have the meanings set forth below, unless a different meaning is clearly required by the context:

(1) “Account” means an account established on the books of the Employer for the purpose of recording amounts credited on behalf of a Participant pursuant to his or her Deferral Elections under the Plan and any income, expenses, gains or losses attributable to the deemed investment of such account in one or more of the Investment Funds.

(2) “Administrator” means the Employer adopting the Plan, or other person designated by the Employer.

(3) “ Affiliated Company ” means (i) the Employer and (ii) and each member of the group of commonly controlled corporations or other businesses that include the Employer, as determined in accordance with Section 414(b) and (c) of the Code and the Treasury Regulations issued thereunder.

(4) “Annual Retainer” means the annual retainer fee payable to an Eligible Director.

(5) “Beneficiary” means the person or persons entitled under Section 10.1 to receive benefits under the Plan upon the death of a Participant.

(6) “Board” means the Board of Directors of the Employer, as constituted from time to time.

(7) “Bonus” means the bonus payable to an Eligible Employee pursuant to the Employer’s corporate bonus program.

(8) “Change of Control” will be deemed, consistent with Section 409A of the Code and the Treasury Regulations issued thereunder, to occur on the date that:

(A) any one person, or more than one person acting as a group (as defined in Treasury Regulation Section 1.409A-3(i)(5)(v)(B)), acquires ownership of stock of the Employer, that together with stock held by such person or group, constitutes more than fifty percent (50%) of the total fair market value or total voting power of the outstanding stock of the Employer; provided, however, that if any one person, or more than one person acting as a group, is considered to own more than fifty percent (50%) of the total fair market value or total voting power of the outstanding stock of the Employer, the acquisition of additional Employer stock by the same person or persons is not considered a Change of Control; or

(B) any one person, or more than one person acting as a group (as defined in Treasury Regulation Section 1.409A-3(i)(5)(v)(B)), acquires (or has acquired during the twelve-month period ending on the date of the most recent acquisition by such person or group) assets from the Employer that have a total “gross fair market value” (as defined in

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Treasury Regulation Section 1.409A-3(i)(5)(vii)(A)) equal to forty percent (40%) or more of the total gross fair market value of all of the assets of the Employer immediately prior to such acquisition or acquisitions; or

(C) any one person, or more than one person acting as a group (as defined in Treasury Regulation Section 1.409A-3(i)(5)(v)(B)), acquires (or has acquired during the twelve-month period ending on the date of the most recent acquisition by such person or group) ownership of stock of the Employer possessing thirty percent (30%) or more of the total voting power of the stock of the Employer; or

(D) a majority of the members of the Board is replaced during any twelve-month period by directors whose appointment or election is not endorsed by a majority of the members of the Board prior to the date of such appointment or election; provided, however, that for purposes of this subparagraph (D), no Change of Control will be deemed to have occurred if any other corporation is a majority stockholder of the Employer.

(9) “Code” means the Internal Revenue Code of 1986, as amended from time to time.

(10) “Compensation” means Salary, Bonus, Commissions and Annual Retainer. Compensation will not include, among other items, employee referral awards or severance payments. In addition, a Participant’s Compensation shall not, for purposes of the Plan, include any item of compensation earned for a period of service rendered prior to the effective date of the Deferral Election filed by the Participant with respect to that item.

(11) “Commissions” mean the commissions earned by an Eligible Employee for services rendered in connection with the direct sale of products or services of the Company or any Affiliated Entity to unrelated parties, with the amount of such commissions to be determined either as a percentage of the purchase price of those products or services or by reference to the volume of those sales.

(12) “Deferral Election” means the irrevocable election filed by the Participant under Article V of the Plan pursuant to which a portion of his or her Compensation for the Plan Year is to be deferred in accordance with the provisions of the Plan.

(13) “Eligible Director” means a non-employee member of the Board.

(14) “Eligible Employee” means any Employee who is either a highly compensated employee of the Employer or other Participating Employer or part of its management personnel, as determined pursuant to guidelines established by the Administrator form time to time.

(15) “ Employee” means any person in the employ of one or more members of the Employer Group, subject to the control and direction of the employer entity as to both the work to be performed and the manner and method of performance.

(16) “Employer” means Gilead Sciences, Inc.

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(17) “Employer Group” means (i) the Employer and (ii) each of the other members of the controlled group of corporations that includes the Employer, as determined in accordance with Sections 414(b) and (c) of the Code, except that in applying Sections 1563(1), (2) and (3) for purposes of determining the controlled group of corporations under Section 414(b), the phrase “at least 50 percent” shall be used instead of “at least 80 percent” each place the latter phrase appears in such sections, and in applying Section 1.414(c)-2 of the Treasury Regulations for purposes of determining trades or businesses that are under common control for purposes of Section 414(c), the phrase “at least 50 percent” shall be used instead of “at least 80 percent” each place the latter phrase appears in Section 1.4.14(c)-2 of the Treasury Regulations.

(18) “ERISA” means the Employee Retirement Income Security Act of 1974, as amended from time to time.

(19) “Extended Deferral Election” means a Participant’s election, made in accordance with the terms and conditions of Section 9.2 of the Plan, to defer the distribution of his or her Account for an additional period of at least five (5) years measured from the date or event on which that Account was scheduled to first become due and payable under the Plan.

(20) “Fee Period” means the applicable period of service over which the Annual Retainer subject to an Eligible Director’s Deferral Election is to be earned and shall be determined in accordance with Section 6.2 of the Plan.

(21) “Identification Date” means each December 31.

(22) “Investment Fund” means any actual investment fund which serves as the measure of the notional investment return on all or any portion of an Account pursuant to the provisions of Section 8.

(23) “Investment Fund Share” means the share, unit, or other evidence of ownership in a designated Investment Fund.

(24) “Participant” means any Eligible Employee or Eligible Director who participates in the Plan through one or more Deferral Elections under Article V.

(25) “Participating Employer” means the Employer and any other Affiliated Company which has, with the consent of the Administrator, adopted this Plan as a deferred compensation program for one or more of its Eligible Employees.

(26) “Phantom Shares” mean an award denominated in shares of the Employer’s common stock pursuant to which the award holder has the right to receive an amount equal to the value of a specified number of shares of the Employer’s common stock at a designated time or over a designated period and which will be payable in such shares issued under the Gilead Sciences, Inc. 2004 Equity Incentive Plan. Phantom Shares shall be a form of deemed investment under the Plan only with respect to the Annual Retainers deferred hereunder by Eligible Directors.

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(27) “Plan” means the Gilead Sciences, Inc. 2005 Deferred Compensation Plan, as set forth in this document and as subsequently amended from time to time.

(28) “Plan Year” means the calendar year.

(29) “Prior Plan” means the Gilead Sciences, Inc. Deferred Compensation Plan, as in effect as of December 31, 2004. No additional Compensation may be deferred under the Prior Plan after December 31, 2004.

(30) “Salary” means an Eligible Employee’s base salary.

(31) “Separation from Service” means, for a Participant who is an Employee, such individual’s cessation of Employee status by reason of his or her death, retirement or termination of employment. Such Participant shall be deemed to have terminated employment at such time as the level of his or her bona fide services to be performed as an Employee (or non-employee consultant or contractor) permanently decreases to a level that is not more than twenty percent (20%) of the average level of services he or she rendered as an Employee during the immediately preceding thirty-six (36) months (or such shorter period for which he or she may have rendered such service). For an Eligible Director, a Separation from Service shall be deemed to occur when such individual ceases to serve as a Board member. Any determination as to Separation from Service, however, shall be made in accordance with the applicable standards of the Treasury Regulations issued under Code Section 409A. In addition to the foregoing, a Separation from Service will not be deemed to have occurred while an Employee is on military leave, sick leave, or other bona fide leave of absence if the period of such leave does not exceed six (6) months or any longer period for which such Employee’s right to reemployment with the Employer is provided either by statute or contract; provided, however, that in the event of an Employee’s leave of absence due to any medically determinable physical or mental impairment that can be expected to result in death or to last for a continuous period of not less than six (6) months and that causes such individual to be unable to perform his or her duties as an Employee, no Separation from Service shall be deemed to occur during the first twenty-nine (29) months of such leave. If the period of leave exceeds six (6) months (or twenty-nine (29) months in the event of disability as indicated above) and the Employee’s right to reemployment is not provided either by statute or contract, then such Employee will be deemed to have Separated from Service on the first day immediately following the expiration of such six (6)-month or twenty-nine (29)-month period.

(32) “Specified Employee” means an Eligible Employee who, at any time during the twelve (12)-month period ending on the applicable Identification Date, is:

(A) an officer of the Employer or any other Affiliated Company having aggregate annual compensation from the Employer and/or one or more other Affiliated Companies greater than the compensation limit in effect at the time under Section 416(i)(1)(A)(i) of the Code, provided that no more than fifty such officers shall be determined to be Key Employees as of any Identification Date;

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(B) a five percent owner of the Employer or any other Affiliated Company ; or

(C) a one percent owner of the Employer or any other Affiliated Company who has aggregate annual compensation from the Company and/or one or more other Affiliated Companies of more than $150,000.

The determination of such Specified Employees shall be in accordance with the applicable standards and requirements of Section 409A of the Code and the Treasury Regulations thereunder. If an Eligible Employee is identified as a Specified Key Employee on a Identification Date, then such Eligible Employee shall be considered a Specified Employee for purposes of the Plan during the period beginning on the first April 1 following the Identification Date and ending on the next March 31.

(33) “Trust” means the trust created by the Employer.

(34) “Trust Agreement” means the agreement between the Employer and the Trustee, as set forth in a separate agreement, under which assets are held, administered, and managed subject to the claims of the Employer’s creditors in the event of the Employer’s insolvency, until paid to the Participants and their Beneficiaries as specified in the Plan.

(35) “Trust Fund” means the property held in the Trust by the Trustee.

(36) “Trustee” means the corporation or individuals appointed by the Employer to administer the Trust in accordance with the Trust Agreement.

(37) “Unforeseeable Emergency” means a severe financial hardship to the Participant resulting from:

(A) An illness or accident of the Participant, the Participant’s spouse or Beneficiary or the Participant’s dependent (as defined in Section 152(a) of the Code); or

(B) Loss of the Participant’s property due to casualty (including the need to rebuild a home following damage to the home not otherwise covered by insurance); or

(C) Other similar extraordinary and unforeseeable circumstances arising as a result of events beyond the control of the Participant.

Financial hardship shall not constitute an Unforeseeable Emergency under the Plan to the extent that it is, or may be, relieved by (i) reimbursement or compensation, by insurance or otherwise, (ii) liquidation of the Participant’s assets to the extent that the liquidation of such assets would not itself cause severe financial hardship, or (iii) cessation of deferrals under the Plan.

(b) Pronouns used in the Plan are in the masculine gender but include the feminine gender unless the context clearly indicates otherwise.

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5.1 Eligibility. The Administrator (acting through an authorized committee of one or more officers or other senior executives) shall have absolute discretion in selecting the Eligible Employees who are to participate in the Plan for each Plan Year. An Eligible Employee selected for participation for any Plan Year must, in order to participate in the Plan for that year, file a timely Deferral Election in accordance with the requirements of Section 6.1. An Eligible Employee who is first selected for participation in the Plan after the start of a Plan Year and who has not otherwise been eligible for participation in any other non-qualified elective account balance plan subject to Code Section 409A and maintained by one or more Affiliated Companies may file a Deferral Election for that Plan Year in accordance with the applicable requirements of Section 6.1. Until such time as the Administrator implements a new policy, any selection of new Participants after the start of the Plan Year will be limited to the first business day of May of that Plan Year. Individuals who are selected for participation in the Plan, whether before or after the start of the Plan Year, shall be promptly notified by their Participating Employer of their eligibility to participate in the Plan. Eligible Directors shall automatically be eligible to participate in the Plan during their period of service in such capacity, and their Deferral Elections shall be subject to the same requirements set forth above for Employee Participants.

5.2 Continuation of Participation . Every Eligible Employee who becomes a Participant may continue to file Deferral Elections under the Plan for one or more subsequent Plan Years until the earliest of (i) his or her exclusion from the Plan upon written notice from the Administrator, (ii) his or her cessation of Eligible Employee status or (iii) the termination of the Plan. The Administrator shall have complete discretion to exclude one or more Eligible Employees from Participant status for one or more Plan Years as the Administrator deems appropriate, including the entire period the Participant continues in Eligible Employee status following such exclusion. However, no such exclusion authorized by the Administrator shall become effective until the first day of the first Plan Year coincident with or next following the date of the Administrator’s determination to exclude the individual from such participation. If any Eligible Employee is excluded from Participant status for one or more Plan Years, then such individual shall not be entitled to defer any part of his or her Compensation for those Plan Years.

5.3 Resumption of Participation Following Separation from Service. If a Participant ceases to be an Eligible Employee or an Eligible Director due to a Separation from Service and thereafter returns to service with the Employer, such individual will again become a Participant as of the first day of the first Plan Year coincident with or next following the date on which he or she resumes Eligible Employee or Eligible Director status, provided such individual files a timely a Deferral Election pursuant to Section 6.1 with respect to that Plan Year. However, a Participant who returns to Eligible Employee or Eligible Director status after a Separation from Service of more than twenty-four (24) months during which he or she was not eligible to defer any Compensation under this Plan or any other any other non-qualified elective account balance plan subject to Code Section 409A and maintained by one or more Affiliated Companies shall, following resumption of such service, be permitted to make a Deferral Election under Section 6.1 in accordance with the requirements applicable to a newly-selected Participant. Notwithstanding the foregoing provisions of this Section 5.3, no returning Eligible Employee shall be eligible to participate in the Plan if the Administrator determines to exclude such individual from participation on or before his or her resumption of service.

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5.4 Cessation or Resumption of Participation Following a Change in Status. If any Participant continues in the service of the Employer Group but ceases to be an Eligible Employee or Eligible Director, the individual will continue to be a Participant until the entire amount of his or her Account balance is distributed. However, any Deferral Elections that may otherwise be in effect for such individual shall not apply to Compensation earned for the period that he or she is not an Eligible Employee or Eligible Director. In the event that the individual subsequently resumes Eligible Employee or Eligible Director status in the same Plan Year, then his or her Deferral Elections for that Plan Year will immediately resume and apply to the Compensation subject to those elections that is earned for the period following such resumption of Eligible Employee or Eligible Director status. In the event that the individual subsequently resumes Eligible Employee or Eligible Director status in a subsequent Plan Year, then he or she will again become eligible to defer his or her Compensation under the Plan as of the first day the first Plan Year coincident with or next following the date of such resumption of Eligible Employee or Eligible Director status, provided such individual files a timely a Deferral Election pursuant to Section 6.1 with respect to that Plan Year. However, an Eligible Employee shall not be eligible to make such a new Deferral Election following his or her resumption of Eligible Employee status in a subsequent Plan Year if the Administrator determines to exclude such individual from participation on or before resumption of such status.

6.1 Deferral Elections for Employee Participants. Each Eligible Employee selected for participation shall have the right to file a Deferral Election with respect to the Salary, Commissions and/or Bonus to be earned by such Participant for service as an Eligible Employee during the Plan Year for which the Deferral Election is made. Each Deferral Election must be made by a written or electronic notice filed with the Administrator or its designate in which the Participant shall indicate the percentage of Salary, Commissions and/or Bonus to be deferred in accordance with the applicable percentage limitations set forth in Section 6.5. The notice must be filed on or before the expiration date of the enrollment period designated by the Administrator for the Plan Year for which the Deferral Election is to be effective, but in no event shall the Administrator allow any Deferral Election to be filed later than the last day of the calendar year immediately preceding the start of the Plan Year for which the Salary, Commissions and/or Bonus subject to that election are to be earned. However, the following special rules shall be in effect for Deferral Elections:

(A) Commissions shall be deemed to be earned as a result of the Participant’s services in the Plan Year in which the sale to which those Commissions relate occurs. Accordingly, such Commissions shall only be deferred under the Plan to the extent the Participant has a Deferral Election covering Commissions for that Plan Year.

(B) The Administrator may allow a Deferral Election with respect to a Bonus which qualifies as performance-based compensation in accordance with the standards and requirements set forth in Section 1.409A-1(e) of the Treasury Regulations to be made by a Participant after the start of the Plan Year (or other performance period) to which that Bonus pertains but not later than by a designated date that is at least six (6) months prior to the end of that Plan Year (or any longer performance period in effect for that Bonus).

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(C) An Eligible Employee who is first selected for participation in the Plan after the start of a Plan Year and who has not otherwise been eligible for participation in any other non-qualified elective account balance plan subject to Code Section 409A and maintained by one or more Affiliated Companies must file his or her initial Deferral Election no later than thirty (30) days after the date he or she is so selected. Such Deferral Election shall only be effective as follows: