Citrix Systems (CTXS)

SECTION 13. DEFINITIONS.

(a) “Board of Directors” shall mean the Board of Directors of the Company, as constituted from time to time.

(b) “Code” shall mean the Internal Revenue Code of 1986, as amended.

(c) “Committee” shall mean a committee of the Board of Directors, as described in Section 2(a).

(d) “Company” shall mean XenSource, Inc., a Delaware corporation.

(e) “Consultant” shall mean a person who performs bona fide services for the Company, a Parent or a Subsidiary as a consultant or advisor, excluding Employees and Outside Directors.

(f) “Disability” shall mean that the Optionee is unable to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment.

(g) “EMI Option” shall mean an Option which is intended at grant to be a qualifying enterprise management incentive option for the purposes of Schedule 5, ITEPA.

(h) “Employee” shall mean any individual who is a common-law employee of the Company, a Parent or a Subsidiary.

(i) “Exercise Price” shall mean the amount for which one Share may be purchased upon exercise of an Option, as specified by the Board of Directors in the applicable Stock Option Agreement.

(j) “Fair Market Value” shall mean the fair market value of a Share, as determined by the Board of Directors in good faith. Such determination shall be conclusive and binding on all persons. In the case of an EMI Option only, Fair Market Value shall have the meaning contained in paragraphs 55 and 56 of Schedule 5, ITEPA.

(k) “Family Member” shall mean (i) 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, (ii) any person sharing the Optionee’s household (other than a tenant or employee), (iii) a trust in which persons described in Clause (i) or (ii) have more than 50% of the beneficial interest, (iv) a foundation in which persons described in Clause (i) or (ii) or the Optionee control the management of assets and (v) any other entity in which persons described in Clause (i) or (ii) or the Optionee own more than 50% of the voting interests.

(l) “ISO” shall mean an employee incentive stock option described in Section 422(b) of the Code.

(m) “ITEPA” shall mean Income Taxes (Earnings and Pensions) Act 2003.

(n) “Nonstatutory Option” shall mean a stock option not described in Sections 422(b) or 423(b) of the Code.

(o) “Option” shall mean an ISO, Nonstatutory Option or EMI Option granted under the Plan and entitling the holder to purchase Shares.

(p) “Optionee” shall mean a person who holds an Option.

(q) “Outside Director” shall mean a member of the Board of Directors who is not an Employee.

(r) “Parent” shall mean any corporation (other than the Company) in an unbroken chain of corporations ending with the Company, if each of the corporations other than the Company owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other corporations in such chain. A corporation that attains the status of a Parent on a date after the adoption of the Plan shall be considered a Parent commencing as of such date.

(s) “Plan” shall mean this XenSource, Inc. 2005 Stock Plan.

(t) “Purchase Price” shall mean the consideration for which one Share may be acquired under the Plan (other than upon exercise of an Option), as specified by the Board of Directors.

(u) “Purchaser” shall mean a person to whom the Board of Directors has offered the right to acquire Shares under the Plan (other than upon exercise of an Option).

(v) “Service” shall mean service as an Employee, Outside Director or Consultant.

(w) “Share” shall mean one share of Stock, as adjusted in accordance with Section 8 (if applicable).

(x) “Stock” shall mean the Common Stock of the Company, with a par value of $0.0001 per Share.

(y) “Stock Option Agreement” shall mean the agreement between the Company and an Optionee that contains the terms, conditions and restrictions pertaining to the Optionee’s Option.

(z) “Stock Purchase Agreement” shall mean the agreement between the Company and a Purchaser who acquires Shares under the Plan that contains the terms, conditions and restrictions pertaining to the acquisition of such Shares.

(aa) “Subsidiary” shall mean any corporation (other than the Company) in an unbroken chain of corporations beginning with the Company, if each of the corporations other than the last corporation in the unbroken chain owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other corporations in such chain. A corporation that attains the status of a Subsidiary on a date after the adoption of the Plan shall be considered a Subsidiary commencing as of such date.

DEFINITIONS

For purposes of this Plan, the following terms shall have the meanings indicated:

2.1 Administrator. “Administrator” means the Board or, if the Board delegates responsibility for any matter to the Committee, the term Administrator shall mean the Committee.

2.2 Affiliated Company. “Affiliated Company” means any “parent corporation” or “subsidiary corporation” of the Company, whether now existing or hereafter created or acquired, as those terms are defined in Sections 424(e) and 424(f) of the Code, respectively.

2.3 Board. “Board” means the Board of Directors of the Company.

2.4 Change in Control. “Change in Control” means:

(a) The acquisition, directly or indirectly, in one transaction or a series of related transactions, by any person or group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934, as amended) of the beneficial ownership of securities of the Company possessing more than fifty percent (50%) of the total combined voting power of all outstanding securities of the Company;

(b) A merger or consolidation in which the Company is not the surviving entity, except for a transaction in which the holders of the outstanding voting securities of the Company immediately prior to such merger or consolidation hold as a result of holding Company securities prior to such transaction, in the aggregate, securities possessing more than fifty percent (50%) of the total combined voting power of all outstanding voting securities of the surviving entity (or the parent of the surviving entity) immediately after such merger or consolidation;

(c) A reverse merger in which the Company is the surviving entity but in which the holders of the outstanding voting securities of the Company immediately prior to such merger hold, in the aggregate, securities possessing less than fifty percent (50%) of the total combined voting power of all outstanding voting securities of the Company or of the acquiring entity immediately after such merger;

(d) The sale, transfer or other disposition (in one transaction or a series of related transactions) of all or substantially all of the assets of the Company, except for a transaction in which the holders of the outstanding voting securities of the Company immediately prior to such transaction(s) receive as a distribution with respect to securities of the Company, in the aggregate, securities possessing more than fifty percent (50%) of the total combined voting power of all outstanding voting securities of the acquiring entity immediately after such transaction(s); or

(e) The approval by the stockholders of a plan or proposal for the liquidation or dissolution of the Company.

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

2.6 Committee. “Committee” means a committee of two or more members of the Board appointed to administer the Plan, as set forth in Section 7.1 hereof.

2.7 Common Stock. “Common Stock” means the Common Stock of the Company, subject to adjustment pursuant to Section 4.2 hereof.

2.8 Consultant. “Consultant” means any consultant or advisor if: (i) the consultant or advisor renders bona fide services to the Company or any Affiliated Company; (ii) the services rendered by the consultant or advisor are not in connection with the offer or sale of securities in a capital-raising transaction and do not directly or indirectly promote or maintain a market for the Company’s securities; and (iii) the consultant or advisor is a natural person who has contracted directly with the Company or any Affiliated Company to render such services.

2.9 Covered Employee. “Covered Employee” means the chief executive officer of the Company (or the individual acting in such capacity) and the four (4) other individuals that are the highest compensated officers of the Company for the relevant taxable year for whom total compensation is required to be reported to stockholders under the Exchange Act. Provisions in this Plan making reference to a Covered Employee shall apply only at such time that the Company is Publicly Held.

2.10 Disability. “Disability” means permanent and total disability as defined in Section 22(e)(3) of the Code. The Administrator’s determination of a Disability or the absence thereof shall be conclusive and binding on all interested parties.

2.11 Effective Date. “Effective Date” means the date on which the Plan is adopted by the Board, as set forth on the first page hereof.

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2.12 Exchange Act. “Exchange Act” means the Securities and Exchange Act of 1934, as amended.

2.13 Exercise Price. “Exercise Price” means the purchase price per share of Common Stock payable upon exercise of an Option.

2.14 Fair Market Value. “Fair Market Value” on any given date means the value of one share of Common Stock, determined as follows:

(a) If the Common Stock is then listed or admitted to trading on a Nasdaq market system or a stock exchange which reports closing sale prices, the Fair Market Value shall be the closing sale price on the date of valuation on such Nasdaq market system or principal stock exchange on which the Common Stock is then listed or admitted to trading, or, if no closing sale price is quoted on such day, then the Fair Market Value shall be the closing sale price of the Common Stock on such Nasdaq market system or such exchange on the next preceding day for which a closing sale price is reported.

(b) If the Common Stock is not then listed or admitted to trading on a Nasdaq market system or a stock exchange which reports closing sale prices, the Fair Market Value shall be the average of the closing bid and asked prices of the Common Stock in the over-the-counter market on the date of valuation.

(c) If neither (a) nor (b) is applicable as of the date of valuation, then the Fair Market Value shall be determined by the Administrator in good faith using any reasonable method of evaluation, which determination shall be conclusive and binding on all interested parties.

2.15 Incentive Option. “Incentive Option” means any Option designated and qualified as an “incentive stock option” as defined in Section 422 of the Code.

2.16 Incentive Option Agreement. “Incentive Option Agreement” means an Option Agreement with respect to an Incentive Option.

DEFINITIONS

For purposes of this Plan, the following terms shall have the meanings indicated:

2.1 Administrator. “Administrator” means the Board or, if the Board delegates responsibility for any matter to the Committee, the term Administrator shall mean the Committee.

2.2 Affiliated Company. “Affiliated Company” means any “parent corporation” or “subsidiary corporation” of the Company, whether now existing or hereafter created or acquired, as those terms are defined in Sections 424(e) and 424(f) of the Code, respectively.

2.3 Board. “Board” means the Board of Directors of the Company.

2.4 Cause. “Cause” means, with respect to a Participant’s Continuous Service, the termination by the Company of such Continuous Service for any of the following reasons:

(a) The continued, unreasonable refusal or omission by the Participant to perform any material duties required of him by the Company if such duties are consistent with duties customary for the position held with the Company;

(b) Any material act or omission by the Participant involving malfeasance or gross negligence in the performance of Participant’s duties to, or material deviation from any of the policies or directives of, the Company;

(c) Conduct on the part of Participant which constitutes the breach of any statutory or common law duty of loyalty to the Company; or

(d) Any illegal act by Participant which materially and adversely affects the business of the Company or any felony committed by Participant, as evidenced by conviction thereof, provided that the Company may suspend Participant with pay while any allegation of such illegal or felonious act is investigated.

2.5 Change in Control. “Change in Control” shall mean (i) the acquisition, directly or indirectly, by any person or group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934, as amended) of the beneficial ownership of securities of the Company possessing more than fifty percent (50%) of the total combined voting power of all outstanding securities of the Company; (ii) a merger or consolidation in which the Company is not the surviving entity, except for a transaction the principal purpose of which is to change the state in which the Company is incorporated; (iii) the sale, transfer or other disposition of all or substantially all of the assets of the Company; (iv) a complete liquidation or dissolution of the Company; or (v) any reverse merger in which the Company is the surviving entity but in which securities possessing more than fifty percent (50%) of the total combined voting power of the Company’s outstanding securities are transferred to a person or persons different from the persons holding those securities immediately prior to such merger.

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

2.7 Committee. “Committee” means a committee of two or more members of the Board appointed to administer the Plan, as set forth in Section 7.1 hereof.

2.8 Common Stock. “Common Stock” means the Common Stock, $.001 par value of the Company, subject to adjustment pursuant to Section 4.2 hereof.

2.9 Continuous Service. “Continuous Service” means (i) employment by either the Company or any Affiliated Company, or by a corporation or a parent or subsidiary of a corporation issuing or assuming a stock option in a transaction to which Section 424(a) of the Code applies, which is uninterrupted except for vacations, illness (except for permanent disability, as defined in Section 22(e)(3) of the Code), or leaves of absence which are approved in writing by the Company or any of such other employer corporations, if applicable, (ii) service as a member of the Board of Directors of the Company or an Affiliated Company until Participant resigns, is removed from office, or Participant’s term of office expires and he or she is not reelected, or (iii) so long as Participant is engaged as a consultant or service provider to the Company or other corporation referred to in clause (i) above. For purposes of this Section 2.9, the determination of which entity constitutes a parent or subsidiary corporation of the Company, or an Affiliated Company, shall be made at the time of the determination of Continuous Service.

2.10 Disability. “Disability” means permanent and total disability as defined in Section 22(e)(3) of the Code. The Administrator’s determination of a Disability or the absence thereof shall be conclusive and binding on all interested parties.

2.11 Effective Date. “Effective Date” means the date on which the Plan is adopted by the Board, as set forth on the first page hereof.

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2.12 Exercise Price. “Exercise Price” means the purchase price per share of Common Stock payable upon exercise of an Option.

2.13 Fair Market Value. “Fair Market Value” on any given date means the value of one share of Common Stock, determined as follows:

(a) If the Common Stock is then listed or admitted to trading on a Nasdaq market system or a stock exchange which reports closing sale prices, the Fair Market Value shall be the closing sale price on the date of valuation on such Nasdaq market system or principal stock exchange on which the Common Stock is then listed or admitted to trading, or, if no closing sale price is quoted on such day, then the Fair Market Value shall be the closing sale price of the Common Stock on such Nasdaq market system or such exchange on the next preceding day on which a closing sale price is quoted.

(b) If the Common Stock is not then listed or admitted to trading on a Nasdaq market system or a stock exchange which reports closing sale prices, the Fair Market Value shall be the average of the closing bid and asked prices of the Common Stock in the over-the-counter market on the date of valuation.

(c) If neither (a) nor (b) is applicable as of the date of valuation, then the Fair Market Value shall be determined by the Administrator in good faith using any reasonable method of evaluation, which determination shall be conclusive and binding on all interested parties.

2.14 Good Reason. “Good Reason” means with respect to a Participant’s voluntary termination of Continuous Service if such termination is the result of any of the following:

(a) A reduction in the amount of his base compensation pay in effect at the time of a Change in Control;

(b) The taking of any action by the Company that would substantially diminish the aggregate value of the benefits provided the Participant under the Participant’s medical, health, accident, disability insurance, life insurance, thrift and retirement plans in which he was participating on the date of a Change in Control, other than any such reduction which is (i) required by law, (ii) implemented in connection with a general concessionary arrangement affecting all employees or affecting the group of employees (of which the Participant is a member) or (iii) generally applicable to all beneficiaries of such plans;

(c) A reduction in duties and responsibilities which results in the Participant no longer having duties customary for the position held with the Company at the time of a Change in Control; or

(d) The Company materially breaches any provision of the Participant’s Stock Option Agreement or Stock Purchase Agreement.

2.15 Incentive Option. “Incentive Option” means any Option designated and qualified as an “incentive stock option” as defined in Section 422 of the Code.

2.16 Incentive Option Agreement. “Incentive Option Agreement” means an Option Agreement with respect to an Incentive Option.