GRAN TIERRA ENERGY INC. OPTION AGREEMENT (NONSTATUARY STOCK OPTION)

Exhibit 99.1

GRAN TIERRA ENERGY INC.

2007 EQUITY INCENTIVE PLAN

OPTION AGREEMENT

(NONSTATUARY STOCK OPTION)

Pursuant to your Option Grant Notice (“Grant Notice”) and this Option Agreement, Gran Tierra Energy Inc. (the “Company”) has granted you an Option under its 2007 Equity Incentive Plan (the “Plan”) to purchase the number of shares of the Company’s Common Stock indicated in your Grant Notice at the exercise price indicated in your Grant Notice. Defined terms not explicitly defined in this Option Agreement but defined in the Plan shall have the same definitions as in the Plan.

The details of your Option are as follows:

1. VESTING. Subject to the limitations contained herein, your Option will vest as provided in your Grant Notice, provided that vesting will cease upon the termination of your Continuous Service.

2. NUMBER OF SHARES AND EXERCISE PRICE. The number of shares of Common Stock subject to your Option and your exercise price per share (in United States dollars) referenced in your Grant Notice may be adjusted from time to time for Capitalization Adjustments.

3. EXERCISE RESTRICTION FOR NON-EXEMPT EMPLOYEES. In the event that you are a United States Employee eligible for overtime compensation under the United States Fair Labor Standards Act of 1938, as amended (i.e., a “Non-Exempt Employee”), you may not exercise your Option until you have completed at least six (6) months of Continuous Service measured from the Date of Grant specified in your Grant Notice, notwithstanding any other provision of your Option.

4. METHOD OF PAYMENT. Payment of the exercise price is due in full upon exercise of all or any part of your option. All amounts due are payable in United States dollars based, if applicable, upon the local currency to United States dollar exchange rate published in The Wall Street Journal on the date of exercise of your option (or, if the date of exercise is not a business day in the United States, the next business day in the United States). You may elect to make payment of the exercise price in cash or by check or in any other manner permitted by your Grant Notice, which may include one or more of the following:

(a) Provided that at the time of exercise the Common Stock is publicly traded and quoted regularly in The Wall Street Journal, pursuant to a program developed under Regulation T as promulgated by the United States Federal Reserve Board that, prior to the issuance of Common Stock, results in either the receipt of cash (or check) by the Company or the receipt of irrevocable instructions to pay the aggregate exercise price to the Company from the sales proceeds.

(b) Provided that at the time of exercise the Common Stock is publicly traded and quoted regularly in The Wall Street Journal, by delivery to the Company (either by actual delivery or attestation) of already-owned shares of Common Stock that are owned free and clear of any liens, claims, encumbrances or security interests, and that are valued at Fair Market Value on the date of exercise. Notwithstanding the foregoing, you may not exercise your option by tender to the Company of Common Stock to the extent such tender would violate the provisions of any law, regulation or agreement restricting the redemption of the Company’s stock.

5. WHOLE SHARES. You may exercise your Option only for whole shares of Common Stock.

6. SECURITIES LAW COMPLIANCE. Notwithstanding anything to the contrary contained herein, you may not exercise your option unless the shares of Common Stock issuable upon such exercise are then registered under the Securities Act or, if such shares of Common Stock are not then so registered, the Company has determined that such exercise and issuance would be exempt from the registration requirements of the Securities Act. The exercise of your option also must comply with other applicable laws and regulations governing your option including, without limitation, the laws and regulations of the United States and your country of residence, and you may not exercise your option if the Company determines that such exercise would not be in material compliance with such laws and regulations.

7. TERM. You may not exercise your Option before the commencement or after the expiration of its term. The term of your Option commences on the Date of Xxxxx and expires upon the earliest of the following:

(a) three (3) months after the termination of your Continuous Service for any reason other than your Disability or death, provided that if during any part of such three (3) month period your Option is not exercisable solely because of the condition set forth in the section above relating to “Securities Law Compliance,” your Option shall not expire until the earlier of the Expiration Date or until it shall have been exercisable for an aggregate period of three (3) months after the termination of your Continuous Service;

(b) twelve (12) months after the termination of your Continuous Service due to your Disability;

(c) eighteen (18) months after your death if you die either during your Continuous Service or within three (3) months after your Continuous Service terminates;

(d) the Expiration Date indicated in your Grant Notice; or

(e) the day before the tenth (10th) anniversary of the Date of Xxxxx.

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8. EXERCISE.

(a) You may exercise the vested portion of your Option (and the unvested portion of your Option if your Grant Notice so permits) during its term by delivering a Notice of Exercise (in a form designated by the Company) together with the exercise price to the Secretary of the Company, or to such other person as the Company may designate, during the Company’s regular business hours, together with such additional documents as the Company may then require.

(b) By exercising your Option you agree that, as a condition to any exercise of your Option, the Company may require you to enter into an arrangement providing for the payment by you to the Company of any tax withholding obligation of the Company arising by reason of (1) the exercise of your Option, (2) the lapse of any substantial risk of forfeiture to which the shares of Common Stock are subject at the time of exercise, or (3) the disposition of shares of Common Stock acquired upon such exercise.

9. TRANSFERABILITY. Your option is not transferable, except by will or by the laws of descent and distribution, and is exercisable during your life only by you. Notwithstanding the foregoing, by delivering written notice to the Company, in a form satisfactory to the Company, you may designate a third party who, in the event of your death, shall thereafter be entitled to exercise your option.

10. OPTION NOT A SERVICE CONTRACT. Your option is not an employment or service contract, and nothing in your option shall be deemed to create in any way whatsoever any obligation on your part to continue in the employ of, or as a consultant to, the Company or an Affiliate, as applicable, or of the Company or an Affiliate to continue your employment or consultancy arrangements. In addition, nothing in your option shall obligate the Company or an Affiliate, their respective stockholders, Boards of Directors, Officers or Employees to continue any relationship that you might have as a Director or Consultant for the Company or an Affiliate.

11. WITHHOLDING OBLIGATIONS.

(a) At the time you exercise your Option, in whole or in part, or at any time thereafter as requested by the Company, you hereby authorize withholding from payroll and any other amounts payable to you, and otherwise agree to make adequate provision for (including by means of a “cashless exercise” pursuant to a program developed under Regulation T as promulgated by the Federal Reserve Board to the extent permitted by the Company), any sums required to satisfy the federal, state, local and foreign tax withholding obligations of the Company or an Affiliate, if any, which arise in connection with the exercise of your Option.

(b) Upon your request and subject to approval by the Company, in its sole discretion, and compliance with any applicable legal conditions or restrictions, the Company may withhold from fully vested shares of Common Stock otherwise issuable to you upon the exercise of your option a number of whole shares of Common Stock having a Fair Market Value, determined by the Company as of the date of exercise, not in excess of the minimum amount of tax required to be withheld by law (or such lower amount as may be necessary to avoid classification of your option as a liability for financial accounting purposes). Any adverse consequences to you arising in connection with such share withholding procedure shall be your sole responsibility.

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(c) You may not exercise your Option unless the tax withholding obligations of the Company and/or any Affiliate are satisfied. Accordingly, you may not be able to exercise your Option when desired even though your Option is vested, and the Company shall have no obligation to issue a certificate for such shares of Common Stock or release such shares of Common Stock from any escrow provided for herein unless such obligations are satisfied.

12. PERSONAL DATA. You understand that your employer, if applicable, the Company, and/or its Affiliates hold certain personal information about you, including but not limited to your name, home address, telephone number, date of birth, national social insurance number, salary, nationality, job title, and details of all shares of Common Stock granted, cancelled, vested, unvested, or outstanding (the “Personal Data”). Certain Personal Data may also constitute “Sensitive Personal Data” within the meaning of applicable local law. Such data include but are not limited to Personal Data and any changes thereto, and other appropriate personal and financial data about you. You hereby provide express consent to the Company or its Affiliates to collect, hold, and process any such Personal Data and Sensitive Personal Data. You also hereby provide express consent to the Company and/or its Affiliates to transfer any such Personal Data and Sensitive Personal Data outside the country in which you are employed or retained, including the United States. The legal persons for whom such Personal Data are intended are the Company and any broker company providing services to the Company in connection with the administration of the Plan. You have been informed of your right to access and correct your Personal Data by applying to the Company representative identified on the Grant Notice.

13. ADDITIONAL ACKNOWLEDGEMENTS. You hereby consent and acknowledge that:

(a) Participation in the Plan is voluntary and therefore you must accept the terms and conditions of the Plan and this option as a condition to participate in the Plan and receive this option.

(b) The Plan is discretionary in nature and the Company can amend, cancel, or terminate it at any time.

(c) This option and any other options under the Plan are voluntary and occasional and do not create any contractual or other right to receive future options or other benefits in lieu of future options, even if similar options have been granted repeatedly in the past.

(d) All determinations with respect to any such future options, including, but not limited to, the time or times when such options are made, the number of shares of Common Stock, and performance and other conditions applied to the options, will be at the sole discretion of the Company.

(e) The value of the shares of Common Stock and this option is an extraordinary item of compensation, which is outside the scope of your employment, service contract or consulting agreement, if any

(f) The shares of Common Stock, this option, or any income derived therefrom are a potential bonus payment not paid in lieu of any cash salary compensation and not part of normal or expected compensation or salary for any purposes, including, but not limited to, calculating any termination, severance, resignation, redundancy, end of service payments, bonuses, long-service awards, life or accident insurance benefits, pension or retirement benefits or similar payments.

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(g) In the event of the involuntary termination of your Continuous Service, your eligibility to receive shares of Common Stock or payments under the option or the Plan, if any, will terminate effective as of the date that you are no longer actively employed or retained regardless of any reasonable notice period mandated under local law, except as expressly provided in the option.

(h) The future value of the shares of Common Stock is unknown and cannot be predicted with certainty.

(i) You do not have, and will not assert, any claim or entitlement to compensation, indemnity or damages arising from the termination of this option or diminution in value of the shares of Common Stock and you irrevocably release the Company, its Affiliates and, if applicable, your employer, if different from the Company, from any such claim that may arise.

(j) The Plan and this option set forth the entire understanding between you, the Company and any Affiliate regarding the acquisition of the shares of Common Stock and supersedes all prior oral and written agreements pertaining to this option.

14. NOTICES. Any notices provided for in your Option or the Plan shall be given in writing or electronically and shall be deemed effectively given upon receipt or, in the case of notices delivered by mail by the Company to you, five (5) days after deposit in the mail, postage prepaid, addressed to you at the last address you provided to the Company.

15. GOVERNING PLAN DOCUMENT. Your Option is subject to all the provisions of the Plan, the provisions of which are hereby made a part of your Option, and is further subject to all interpretations, amendments, rules and regulations, which may from time to time be promulgated and adopted pursuant to the Plan. In the event of any conflict between the provisions of your Option and those of the Plan, the provisions of the Plan shall control.

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