ANTIGENICS INC. [INCENTIVE] STOCK OPTIONAGREEMENT [STAGED EXERCISABILITY]

EXHIBIT 10.3

ANTIGENICS INC.

[INCENTIVE] STOCK OPTION AGREEMENT [STAGED EXERCISABILITY]

Antigenics Inc., a Delaware corporation, (the “Company”) hereby grants the following stock option pursuant to its 2009 Equity Incentive Plan. The terms and conditions attached hereto are also a part hereof.

Name of optionee (the “Optionee”):

Date of this option grant:

Number of shares of the Company’s Common Stock subject to this option (“Shares”):

Option exercise price per share:

Number, if any, of Shares that may be purchased on or after the grant date:

Shares that are subject to vesting schedule:

Vesting Start Date:

Vesting Schedule: As indicated online on the Stock Option Plan Summary Page of your Fidelity Account

All vesting is dependent on the continuation of a Business Relationship with the Company, as provided herein.

ANTIGENICS INC.

[INCENTIVE] STOCK OPTION AGREEMENT — INCORPORATED TERMS AND CONDITIONS

This option grant by ANTIGENICS INC. (the “Company”) is subject to the following terms and conditions:

1. Grant Under Plan. This option is granted pursuant to and is governed by the Company’s 2009 Equity Incentive Plan (the “Plan”) and, unless the context otherwise requires, terms used herein shall have the same meaning as in the Plan. This option does not set forth all of the terms and conditions of the Plan, which are incorporated herein by reference. The Board administers the Plan and its determinations regarding the operation of the Plan are final and binding.

2. Grant as Incentive Stock Option [Non-Qualified Stock Option]. This option is intended to qualify as an [This option is a non-statutory stock option and is not intended to qualify as an] incentive stock option under Section 422 of the Internal Revenue Code of 1986, as amended, and the regulations thereunder (the “Code”).

3. Vesting of Option if Business Relationship Continues. The Optionee may exercise this option on or after the date of this option grant for the number of shares of Common Stock, if any, set forth on the cover page hereof. If the Optionee has continuously maintained a Business Relationship (as defined below) with the Company through the dates listed on the vesting schedule set forth on the cover page hereof, the Optionee may exercise this option for the additional number of shares of Common Stock set opposite the applicable vesting date. Notwithstanding the foregoing, the Board may, in its discretion, accelerate the date that any installment of this option or portion thereof becomes exercisable. The foregoing rights are cumulative and may be exercised only before the date which is ten (10) years from the date of this option grant.

4. Termination of Business Relationship.

(a) Termination. If the Optionee’s Business Relationship with the Company ceases, voluntarily or involuntarily, with or without cause, no further installments of this option shall become exercisable, and this option shall expire (may no longer be exercised) after the passage of three months from the date of termination, unless in the case of death or disability, but in no event later than the scheduled expiration date; [provided that, in the case of members of the Board of Directors, if (i) the Optionee has been a member of the Board for at least three years immediately preceding such termination; and (ii) such Optionee declines to stand for re-election at the expiration of his or her current term as a director, then such rights shall be exercisable by the Optionee for a period of 36 months from the date of termination or, if shorter, until the scheduled expiration of this option.] “Business Relationship” means service to the Company or its successor in the capacity of an employee, officer, director or consultant. Any determination under this agreement as to the status of a Business Relationship or other matters referred to above shall be made in good faith by the Board.

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(b) Employment Status. For purposes hereof, with respect to employees of the Company, employment shall not be considered as having terminated during any leave of absence if such leave of absence has been approved in writing by the Company. For purposes hereof, a termination of employment followed by another Business Relationship shall be not be deemed a termination of the Business Relationship unless otherwise provided by the Company. This option shall not be affected by any change of employment within or among the Company and its Subsidiaries so long as the Optionee continuously remains an employee of the Company or any Subsidiary.

5. Death; Disability.

(a) Death. Upon the death of the Optionee while the Optionee is maintaining a Business Relationship with the Company, this option may be exercised, to the extent otherwise exercisable on the date of the Optionee’s death, by the Optionee’s estate, personal representative or beneficiary to whom this option has been transferred pursuant to Section 9, only at any time within twelve (12) months after the date of death, but not later than the scheduled expiration date.

(b) Disability. If the Optionee ceases to maintain a Business Relationship with the Company by reason of his or her disability, this option may be exercised, to the extent otherwise exercisable on the date of cessation of the Business Relationship, only at any time within twelve (12) months after such cessation of the Business Relationship, but not later than the scheduled expiration date. For purposes hereof, “disability” means “permanent and total disability” as defined in Section 22(e)(3) of the Code.

6. Partial Exercise. This option may be exercised in part at any time and from time to time within the above limits, except that this option may not be exercised for a fraction of a share.

7. Securities Laws Restrictions on Resale. It shall be a condition to the Optionee’s right to purchase shares of Common Stock hereunder that the Company may, in its discretion, require (a) that the shares of Common Stock reserved for issuance upon the exercise of this Option shall have been duly listed, upon official notice of issuance, upon any national securities exchange or automated quotation system on which the Company’s Common Stock may then be listed or quoted, (b) that either (i) a registration statement under the Securities Act of 1933, as amended, or any successor statute (the “Securities Act”) with respect to said shares shall be in effect, or (ii) in the opinion of counsel for the Company the proposed purchase shall be exempt from registration under the Securities Act and the Optionee shall have made such undertakings and agreements with the Company as the Company may reasonably require, and (c) that such other steps, if any, as counsel for the Company shall consider necessary to comply with any law applicable to the issuance of such shares by the Company shall have been taken by the Company or the Optionee, or both. The certificates representing the shares purchased under this Option may contain such legends as counsel for the Company shall deem necessary to comply with any applicable law. If any Shares are held in book-entry form, the Company may take such steps as it deems necessary or appropriate to record and manifest the restrictions applicable to such Shares.

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8. Method of Exercising Option. Subject to the terms and conditions of this agreement, this option may be exercised by written notice to the Company at its principal executive office, or to such transfer agent as the Company shall designate. Such notice shall state the election to exercise this option and the number of Shares for which it is being exercised and shall be signed by the person or persons so exercising this option. Such notice shall be accompanied by payment of the full purchase price of such shares, and the Company shall deliver a certificate or certificates representing such shares as soon as practicable after the notice shall be received. Such certificate or certificates shall be registered in the name of the person or persons so exercising this option (or, if this option shall be exercised by the Optionee and if the Optionee shall so request in the notice exercising this option, shall be registered in the name of the Optionee and another person jointly, with right of survivorship). In the event this option shall be exercised, pursuant to Section 5 hereof, by any person or persons other than the Optionee, such notice shall be accompanied by appropriate proof of the right of such person or persons to exercise this option.

9. Option Not Transferable. This option is not transferable or assignable except by will or by the laws of descent and distribution. During the Optionee’s lifetime only the Optionee can exercise this option.

10. No Obligation to Exercise Option. The grant and acceptance of this option imposes no obligation on the Optionee to exercise it.

11. No Obligation to Continue Business Relationship. Neither the Plan, this agreement, nor the grant of this option imposes any obligation on the Company to continue the Optionee in employment or any other Business Relationship.

12. Adjustments. Except as is expressly provided in the Plan with respect to certain changes in the capitalization of the Company, no adjustment shall be made for dividends or similar rights for which the record date is prior to such date of exercise.

13. Withholding Taxes. If the Company in its discretion determines that it is obligated to withhold any tax in connection with the exercise of this option, or in connection with the transfer of, or the lapse of restrictions on, any Common Stock or other property acquired pursuant to this option, the Optionee hereby agrees that the Company may withhold from the Optionee’s wages or other remuneration the appropriate amount of tax. At the discretion of the Company, the amount required to be withheld may be withheld in cash from such wages or other remuneration or in kind from the Common Stock or other property otherwise deliverable to the Optionee on exercise of this option. The Optionee further agrees that, if the Company does not withhold an amount from the Optionee’s wages or other remuneration sufficient to satisfy the withholding obligation of the Company, the Optionee will make reimbursement on demand, in cash, for the amount underwithheld.

14. Early Disposition. The Optionee agrees to notify the Company in writing immediately after the Optionee transfers any Shares, if such transfer occurs on or before the later of (a) the date that is two years after the date of this agreement or (b) the date that is one year after the date on which the Optionee acquired such Shares. The Optionee also agrees to provide the Company with any information concerning any such transfer required by the Company for tax purposes. [Note: The foregoing is for ISOs only.]

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15. Arbitration. Any dispute, controversy, or claim arising out of, in connection with, or relating to the performance of this agreement or its termination shall be settled by arbitration in the Commonwealth of Massachusetts, pursuant to the rules then obtaining of the American Arbitration Association. Any award shall be final, binding and conclusive upon the parties and a judgment rendered thereon may be entered in any court having jurisdiction thereof.

16. Provision of Documentation to Optionee. By signing this agreement the Optionee acknowledges receipt of a copy of this agreement and a copy of the Plan.

17. Miscellaneous.

(a) Notices. All notices hereunder shall be in writing and shall be deemed given when sent by mail, if to the Optionee, to the address set forth on the cover page or to the address shown on the records of the Company, and if to the Company, to the Company’s principal executive offices, attention of the Corporate Secretary.

(b) Entire Agreement; Modification. This agreement and the Plan constitute the entire agreement between the parties relative to the subject matter hereof, and supersede all proposals, written or oral, and all other communications between the parties relating to the subject matter of this agreement. This agreement may be modified, amended or rescinded only by a written agreement executed by both parties.

(c) Fractional Shares. If this option becomes exercisable for a fraction of a share because of the adjustment provisions contained in the Plan, such fraction shall be rounded as provided by the Board.

(d) Issuances of Securities; Changes in Capital Structure. Except as expressly provided herein or in the Plan, no issuance by the Company of shares of stock of any class, or securities convertible into shares of stock of any class, shall affect, and no adjustment by reason thereof shall be made with respect to, the number or price of shares subject to this option. No adjustments need be made for dividends paid in cash or in property other than securities of the Company. If there shall be any change in the Common Stock of the Company through merger, consolidation, reorganization, recapitalization, stock dividend, stock split, share exchange, spin-off, split-up or other similar change in capitalization or event, the restrictions contained in this agreement shall apply with equal force to the additional and/or substitute securities, if any, received by the Optionee in exchange for, or by virtue of his or her ownership of, Shares, except as otherwise determined by the Board.

(e) Severability. The invalidity, illegality or unenforceability of any provision of this agreement shall in no way affect the validity, legality or enforceability of any other provision.

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(f) Successors and Assigns. This agreement shall be binding upon and inure to the benefit of the parties hereto and their respective successors and assigns, subject to the limitations set forth in Section 9 hereof.

(g) Governing Law. This agreement shall be governed by and interpreted in accordance with the laws of the State of Delaware, without giving effect to the principles of the conflicts of laws thereof.

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