ICAGEN, INC. Nonstatutory Stock Option Agreement

Exhibit 10.4

ICAGEN, INC.

Nonstatutory Stock Option Agreement

Granted Under 2004 Stock Incentive Plan

[FOR DIRECTOR OPTIONS]

[NOTE: Such director options may only be granted to the individual who is director]

This agreement evidences the grant by Icagen, Inc., a Delaware corporation (the “Company”), on                     , 200   (the “Grant Date”) to                     , a director of the Company (the “Participant”), of an option to purchase, in whole or in part, on the terms provided herein and in the Company’s 2004 Stock Incentive Plan (the “Plan”), a total of                      shares (the “Shares”) of common stock, $0.001 par value per share, of the Company (“Common Stock”) at $             per Share. Unless earlier terminated, this option shall expire at 5:00 p.m., Eastern time, on                      (the “Final Exercise Date”).

It is intended that the option evidenced by this agreement shall not be an incentive stock option as defined in Section 422 of the Internal Revenue Code of 1986, as amended, and any regulations promulgated thereunder (the “Code”). Except as otherwise indicated by the context, the term “Participant”, as used in this option, shall be deemed to include any person who acquires the right to exercise this option validly under its terms.

This option will become exercisable (“vest”) as to 100% of the original number of Shares on the Grant Date.

(a) Form of Exercise. Each election to exercise this option shall be in writing, signed by the Participant, and received by the Company at its principal office, accompanied by this agreement, and payment in full as follows:

(1) in cash or by check, payable to the order of the Company;

(2) by (i) delivery of an irrevocable and unconditional undertaking by a creditworthy broker to deliver promptly to the Company sufficient funds to pay the exercise price and any required tax withholding or (ii) delivery by the Participant to the Company of a copy of irrevocable and unconditional instructions to a creditworthy broker to deliver promptly to the Company cash or a check sufficient to pay the exercise price and any required tax withholding;

(3) with the approval of the Board, when the Common Stock is registered under the Exchange Act, by delivery of shares of Common Stock owned by the Participant valued at their fair market value as determined by (or in a manner approved by) the Board in good faith (“Fair Market Value”), provided (i) such method of payment is then permitted under applicable law and (ii) such Common Stock, if acquired directly from the Company, was owned by the Participant at least six months prior to such delivery;

(4) to the extent permitted by applicable law and by the Board, in its sole discretion by (i) delivery of a promissory note of the Participant to the Company on terms determined by the Board, or (ii) payment of such other lawful consideration as the Board may determine; or

(5) by any combination of the above permitted forms of payment.

The Participant may purchase less than the number of shares covered hereby, provided that no partial exercise of this option may be for any fractional share.

(b) Exercise Period. The right to exercise this option shall terminate on the Final Exercise Date. Notwithstanding the foregoing, if the Participant, prior to the Final Exercise Date, violates the non-competition or confidentiality provisions of any employment contract, confidentiality and nondisclosure agreement or other agreement between the Participant and the Company, the right to exercise this option shall terminate immediately upon such violation.

The Participant agrees, in connection with an underwritten public offering of the Company’s securities pursuant to a registration statement under the Securities Act, (i) not to sell, make short sale of, loan, grant any options for the purchase of, or otherwise dispose of any shares of Common Stock held by the Participant (other than those shares included in the offering) without the prior written consent of the Company or the underwriters managing such initial underwritten public offering of the Company’s securities for such number of days (not to exceed 180 days) from the effective date of such registration statement as the Company or the managing underwriters may require, and (ii) to execute any agreement reflecting clause (i) above as may be requested by the Company or the managing underwriters at the time of such offering.

No Shares will be issued pursuant to the exercise of this option unless and until the Participant pays to the Company, or makes provision satisfactory to the Company for payment of, any federal, state or local withholding taxes required by law to be withheld in respect of this option. When the Common Stock is registered under the Exchange Act, Participant may satisfy such tax obligations in whole or in part by delivery of shares of Common Stock owned by Participant valued at their Fair Market Value; provided, however, that the total tax withholding where stock is being used to satisfy such tax obligations cannot exceed the Company’s minimum statutory withholding obligations (based on minimum statutory withholding rates for federal and state tax purposes, including payroll taxes, that are applicable to such supplemental taxable

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income). The Company may, to the extent permitted by law, deduct any such tax obligations from any payment of any kind otherwise due to Participant.

This option may not be sold, assigned, transferred, pledged or otherwise encumbered by the Participant, either voluntarily or by operation of law, except by will or the laws of descent and distribution, and, during the lifetime of the Participant, this option shall be exercisable only by the Participant.

This option is subject to the provisions of the Plan, a copy of which is furnished to the Participant with this option.

IN WITNESS WHEREOF, the Company has caused this option to be executed under its corporate seal by its duly authorized officer. This option shall take effect as a sealed instrument.

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PARTICIPANT’S ACCEPTANCE

The undersigned hereby accepts the foregoing option and agrees to the terms and conditions thereof. The undersigned hereby acknowledges receipt of a copy of the Company’s 2004 Stock Incentive Plan.

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