AMENDED AND RESTATED INCENTIVE STOCK OPTION AND NONSTATUTORY STOCK OPTION PLAN

Exhibit 10.4

EMBREX, INC.

AMENDED AND RESTATED INCENTIVE STOCK OPTION

AND NONSTATUTORY STOCK OPTION PLAN

RESTRICTED STOCK UNIT AGREEMENT

This Restricted Stock Unit Agreement (“Agreement”) dated as of                      , 20      (the “Date of Grant”) is entered into by and between Embrex, Inc., a North Carolina corporation (the “Company”), and                               (the “Grantee”).

Unless otherwise defined herein, the terms defined in the Amended and Restated Incentive Stock Option and Nonstatutory Stock Option Plan, as amended (the “Plan”) shall have the same defined meanings in this Restricted Stock Unit Agreement.

1. Grant of Stock Units . Subject to this Agreement and the Amended and Restated Incentive Stock Option and Nonstatutory Stock Option Plan of the Company, as amended (the “Plan”), the terms of which are incorporated herein by this reference, the Company hereby grants to Grantee, and Grantee hereby accepts, restricted stock units (“Stock Units”) as set forth herein. Each Stock Unit granted hereby entitles the Grantee to receive one share of common stock of the Company, $.01 par value per share (the “Common Stock”), as follows:

2. Vesting . Subject to acceleration pursuant to Section 5 below, the Stock Units shall vest and become nonforfeitable as follows: If the Grantee is an employee, officer, consultant or advisor of the Company on the Date of Grant and continues to provide services to the Company (or any Parent or Subsidiary) in the same status through the vesting dates, 25% of the Stock Units shall vest on each of the first four anniversaries of the Vesting Commencement Date. Subject to the provisions of any employment, severance or similar agreement to the contrary between the Grantee and the Company or any Parent or Subsidiary, if the Grantee is an employee of the Company (or any Parent or Subsidiary) on the Date of Grant and ceases to be such an employee but continues to provide services as a non-employee director, consultant or advisor, the Grantee shall forfeit any Stock Units that are unvested on the date of the change in the Grantee’s status. If on the Date of Grant the Grantee is not an employee of the Company (or any Parent or Subsidiary of the Company) and becomes such an employee during the vesting period, the vesting of the Stock Units shall not be affected by such a change of status.

3. Delivery of Shares .

(a) General . The Stock Units shall automatically be converted into shares of Common Stock as they vest (or upon such later date elected pursuant to Section 4 below). Certificates representing such shares shall be delivered to the Grantee as soon as practicable thereafter, in written or electronic form as the Committee may determine.

(b) Legal Restrictions . No shares shall be delivered unless such delivery complies with the applicable registration requirements of the Securities Act of 1933, as amended, any applicable listing requirement of any national securities exchange on which stock of the same class is then listed, and any other requirements of federal, state or local law or of any regulatory bodies having jurisdiction over such issuance and exercise. Assuming such compliance, for tax purposes shares shall be considered issued to the Grantee on the date of vesting or the deferred date of delivery, as applicable.

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4. Deferral Election Agreement . The Grantee may elect to defer the date the Stock Units are converted into shares of Common Stock and such shares are delivered by completing and submitting to the Company a deferral election in the form attached hereto as Exhibit A at the time the Grantee enters into this Agreement. The Committee shall, in its sole discretion, establish the further rules and procedures for such deferral elections.

5. Acceleration of Vesting . Upon the occurrence of (i) any of the events described in Section 18 of the Plan that cause the vesting of awards granted under the Plan to accelerate or (ii) any other event described in another agreement then in effect between the Company and Grantee that causes the vesting of awards granted under the Plan to accelerate, any Stock Units that are not vested at such time shall become fully vested, in addition to any Stock Units that previously have vested.

6. Nature of Grant . By signing this Agreement, the Grantee acknowledges that:

(a) The Company has established the Plan voluntarily, it is discretionary in nature and the Company may modify, amend, suspend or terminate it at any time, unless otherwise provided in the Plan and this Agreement;

(b) The grant of the Stock Units is voluntary and occasional and does not create any contractual or other right to receive future grants of Stock Units, or benefits in lieu of Stock Units, even if Stock Units have been granted repeatedly in the past;

(c) All decisions with respect to future grants of Stock Units, if any, shall be at the sole discretion of the Company;

(d) The Grantee’s participation in the Plan shall not create a right to further employment or service with the Grantee’s employer (the “Employer”) and shall not interfere with the ability of the Employer to terminate the Grantee’s service relationship at any time, with or without cause;

(e) The Grantee is voluntarily participating in the Plan;

(f) The Stock Units are an extraordinary item that is outside the scope of the Grantee’s employment or service contract, if any, and that does not constitute compensation of any kind for services of any kind rendered to the Company or the Employer;

(g) The Stock Units are not part of normal or expected compensation or salary for any purposes, including, but not limited to, calculating any severance, resignation, termination, redundancy, end of service payments, bonuses, long-service awards, pension or retirement benefits or similar payments;

(h) In the event that the Grantee is not an employee of the Company, the grant of the Stock Units will not be interpreted to form an employment contract or relationship with the Company or any Parent or Subsidiary or the Employer;

(i) The future value of the underlying shares is unknown and cannot be predicted with certainty;

(j) If shares are delivered on vesting of the Stock Units, or if the Grantee elects to defer delivery of the shares, the shares in either case may increase or decrease in value, even below their value on the date of grant or the date(s) of vesting;

(k) In consideration of the grant of the Stock Units, no claim or entitlement to compensation or damages shall arise from termination of the Stock Units or diminution in value of the Stock Units or shares purchased through exercise of the Stock Units resulting from termination of the Grantee’s employment or other service by the Company or the Employer (for any reason whatsoever and whether or not in breach of local labor laws), and the Grantee irrevocably releases the Company and the Employer from any such claim that may arise; if, notwithstanding the foregoing, any such claim is found by a court of competent jurisdiction to have arisen, then, by signing this Agreement, the Grantee shall be deemed irrevocably to have waived his or her entitlement to pursue such claim; and

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(l) Notwithstanding any terms or conditions of the Plan to the contrary, in the event of involuntary termination of the Grantee’s employment or other service (whether or not in breach of local labor laws), the Grantee’s right to receive the Stock Units and vest in the Stock Units under the Plan, if any, will terminate effective as of the date of such termination and will not be extended by any notice period mandated under local law ( e.g. , active employment or service would not include a period of “garden leave” or similar period pursuant to local law); the Committee shall have the exclusive discretion to determine whether the Grantee’s status as a service provider has terminated for purposes of this Agreement.

7. Restrictions on Transfer . Until the shares of Common Stock subject to the Stock Units have been delivered, neither the Stock Units nor the shares or any beneficial interest therein may be transferred, encumbered or otherwise alienated at any time. Any attempt to do so contrary to the provisions hereof shall be null and void.

8. Rights as a Shareholder . The Grantee shall not have voting or any other rights as a shareholder with respect to the Stock Units prior to the settlement of the Stock Units and delivery of the underlying shares of Common Stock.

9. Responsibility of U.S. Grantees for Taxes . If the Grantee is subject to taxation under the laws of the U.S., the Grantee shall be required to deposit with the Company an amount of cash equal to the amount determined by the Company to be required with respect to any withholding taxes, FICA contributions, or the like under any federal, state, or local tax or other statute, ordinance, rule or regulation in connection with the award, deferral, or settlement of the Stock Units. Alternatively, the Company may, in its sole discretion, withhold the required amounts from the Employee’s pay during the pay periods next following the date on which any applicable tax liability arises. The Committee, in its discretion, may permit the Grantee, subject to such conditions as the Committee shall require, to elect to have the Company withhold a number of shares of Common Stock otherwise deliverable having a fair market value sufficient to satisfy the statutory minimum of all or part of the Grantee’s estimated total federal, state, and local tax obligations associa