FORM OF STOCK OPTION AGREEMENT POTBELLY CORPORATION 2004 EQUITYINCENTIVE PLAN

Exhibit 10.13

FORM OF STOCK OPTION AGREEMENT

POTBELLY CORPORATION

2004 EQUITY INCENTIVE PLAN

THIS STOCK OPTION AGREEMENT ¨ POTBELLY CORPORATION 2004 EQUITY INCENTIVE PLAN (this “Agreement”) is made in Chicago, Illinois by and between [Insert Name of Director] (the “Director”) and POTBELLY CORPORATION, a Delaware corporation (the “Company”).

Recitals

A. The Company has implemented the Potbelly Corporation 2004 Equity Incentive Plan which, together with any amendments thereto, is hereinafter referred to as the “Plan”.

B. The Company desires to grant to the Director options (the “Options”) to purchase from the Company shares of the Company’s Common Stock, $.01 par value per share (the “Common Stock”), pursuant to the Plan.

Agreements

NOW THEREFORE, in consideration of the prior recitals, the Company hereby grants to the Director, and the Director hereby accepts, the Options immediately described below on the terms and conditions contained herein.

The Options shall vest and, subject and pursuant to the provisions of the Plan and this Agreement (including the immediately following paragraph), shall be exercisable to the extent of [Insert Applicable Vesting Schedule].

THE OPTIONS, AND THE RIGHTS AND OBLIGATIONS OF THE DIRECTOR AND THE COMPANY WITH RESPECT TO THE OPTIONS (INCLUDING WITHOUT LIMITATION PROVISIONS GOVERNING THE DIRECTOR’S ABILITY TO EXERCISE THE OPTIONS), ARE SUBJECT TO THE PLAN AND THE TERMS AND CONDITIONS OF THIS AGREEMENT ATTACHED HERETO (THE “TERMS AND CONDITIONS”), BOTH OF WHICH ARE INCORPORATED HEREIN BY REFERENCE.

Except as otherwise expressly provided in the Terms and Conditions, the Options may not be exercised prior to the consummation of the Company’s initial public offering of Common Stock issued pursuant to a registration statement declared effective under the Securities Act of 1933 (“IPO”).

This grant of Options shall be null and void unless the Director accepts this Agreement by executing it in the space provided below and returning an original executed copy to the Company on or before [Insert Date]. This Agreement may be executed in two counterparts each of which shall be deemed an original and both of which together shall constitute one and the same instrument.

Initially capitalized terms used but not defined in this Agreement have the same meanings given them in the Plan.

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IN WITNESS WHEREOF, the Company and the Director have duly executed this Agreement as of the dates set forth below.

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TERMS AND CONDITIONS OF STOCK OPTION AGREEMENT

1. Exercise of Options.

1.1 The Options may be exercised (to the extent vested) by giving written notice to the Committee specifying the number of whole shares of Common Stock to be purchased and accompanied by payment therefore in full using such method of payment as the Committee in its sole and absolute discretion deems appropriate.

1.2 Except as otherwise provided in Section 3 or Section 4, the Options may not be exercised prior to the consummation of the Company’s initial public offering of Common Stock issued pursuant to a registration statement declared effective under the Securities Act of 1933 (“IPO”).

2. Termination of Option. In no event may the Options be exercised after they terminate as set forth in this Section 2.

2.1 If, prior to the Company’s IPO, the Director’s membership on the Board of Directors of the Company terminates for any reason whatsoever, then the unvested Options shall immediately terminate and may not be exercised.

2.2 If, after the consummation of the Company’s IPO:

2.3 Notwithstanding anything in this Agreement to the contrary, the Options shall terminate, to the extent not exercised or earlier terminated, on the Expiration Date.

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3. Corporate Transaction. In the event of a Corporate Transaction (as defined in the Plan), the Board (as constituted immediately prior to such Corporate Transaction) may, in its sole and absolute discretion, take any one or more of the following actions with respect to the Options:

(a) provide that the Options shall be assumed, or equivalent options shall be substituted, by the acquiring or succeeding corporation or entity (of an affiliate thereof); provided, however, that any such options substituted for incentive stock options shall meet the requirements of Section 422(a) of the Code;

(b) upon written notice to the Director, provide that (i) all vested but unexercised Options will terminate immediately prior to the consummation of such Corporate Transaction unless exercised by the optionee within a specified period following the date of such notice and prior to the consummation of such Corporate Transaction, and (ii) all unvested Options will terminate upon consummation of such Corporate Transaction;

(c) in the event of a merger or consolidation under the terms of which holders of the Common Stock of the Company will receive upon consummation thereof a cash payment for each share surrendered in the merger or consolidation (the “Merger Price”), make or provide for a cash payment to the Director, in exchange for the termination of such options, equal to the difference between (i) the Merger Price times the number of shares of Common Stock subject to any vested Options whose exercise price is less than the Merger Price (“In the Money Options”), and (ii) the aggregate exercise price of all such In the Money Options; or

(d) provide that all or any outstanding Options shall vest in full immediately prior to such Corporate Transaction and shall terminate immediately following such Corporate Transaction.

4. Ability to Exercise prior to the Company’s IPO. After the date hereof the Board may determine, in its sole and absolute discretion, to permit the Director to exercise vested Options prior to the consummation of the Company’s IPO (hereinafter referred to as a “Pre-IPO Exercise”). If the Board makes a determination in the future to permit a Pre-IPO Exercise, then (a) the terms governing such exercise, and (b) the shares of Common Stock acquired by the Director upon any such exercise, shall be governed in accordance with the terms and provisions set forth on Schedule I hereto, which is deemed to be an integral part of this Agreement. The Director hereby (x) acknowledges and agrees that the Board is under no obligation (legal or otherwise) to permit a Pre-IPO Exercise, and (y) covenants and agrees that any shares of Common Stock acquired pursuant to a Pre-IPO Exercise shall be subject to the terms and conditions set forth on Schedule I.

5. Initial Public Offering Lock-Up. The Director hereby agrees that in the event of the Company’s IPO, the Director shall not offer, sell, contract to sell, pledge, hypothecate, grant any option to purchase or make any short sale of, or otherwise dispose of, any shares of capital stock of the Company (or any rights to acquire capital stock of the Company) then held by such Director (including without limitation any shares of Common Stock acquired via an exercise of the Options, irrespective of whether such exercise occurred before or after the consummation of such IPO) for such period of time as may be established by the managing underwriter therefore; provided, however, that such period of time shall not exceed 180 days after the consummation of such IPO.

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SCHEDULE I

PRE-IPO SHARES

Any shares of Common Stock acquired pursuant to a Pre-IPO Exercise (hereinafter referred to in this Schedule I as “Pre-IPO Shares”) shall be governed in accordance with the terms and provisions of this Schedule I.

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