GERON CORPORATION 2006 DIRECTORS' STOCK OPTION PLAN

(a)

“ Award ” shall mean an Option, a Restricted Stock award or a Restricted Stock Unit award granted to an Outside Director pursuant to the Plan.

(b)

“ Award Agreement ” shall mean any written agreement, contract or other instrument or document evidencing an Award, including through electronic medium.

(c)

“ Board ” shall mean the Board of Directors of the Company.

(d)

“ Code ” shall mean the Internal Revenue Code of 1986, as amended.

(e)

“ Common Stock ” shall mean the Common Stock of the Company.

(f)

“ Company ” shall mean Geron Corporation, a Delaware corporation.

(g)

“ Continuous Status as a Director ” shall mean the absence of any interruption or termination of service as a Director.

(h)

“ Director ” shall mean a member of the Board.

(i)

“ Employee ” shall mean any person, including officers and directors, employed by the Company or any Parent or Subsidiary of the Company. The payment of a director’s fee by the Company shall not be sufficient in and of itself to constitute “employment” by the Company.

(j)

“ Exchange Act ” shall mean the Securities Exchange Act of 1934, as amended.

(k)

“ Option ” shall mean a stock option granted pursuant to the Plan. All Options shall be nonqualified stock options (i.e., options that are not intended to qualify as incentive stock options under Section 422 of the Code).

(l)

“ Outside Director ” shall mean a Director who is not an Employee.

(m)

“ Parent ” shall mean a “parent corporation”, whether now or hereafter existing, as defined in Section 424(e) of the Code.

(n)

“ Participant ” shall mean an Outside Director who receives an Award.

(o)

“ Plan ” shall mean this 2006 Directors’ Stock Option Plan, as it may be amended from time to time.

(p)

“ Restricted Stock ” shall mean an Award of Shares granted to an Outside Director pursuant to Section 5 or Section 11.

(q)

“ Restricted Stock Unit ” shall mean an Award granted pursuant to Section 12.

(r)

“ Share ” shall mean a share of the Common Stock, as adjusted in accordance with Section 14 of the Plan.

(s)

“ Subsidiary ” shall mean a “subsidiary corporation”, whether now or hereafter existing, as defined in Section 424(f) of the Code.

(a)

Administrator . Except as otherwise required herein, the Plan shall be administered by the Board.

(b)

Procedure for Grants . All grants of Options and Restricted Stock pursuant to Section 5 shall be automatic and non-discretionary and shall be made strictly in accordance with the provisions set forth in Section 5. In addition, the Board may make discretionary grants of Options, Restricted Stock or Restricted Stock Units.

(c)

Powers of the Board . Subject to the provisions and restrictions of the Plan, the Board shall have the authority, in its discretion: (i) to determine, upon review of relevant information and in accordance with Section 9(b) of the Plan, the fair market value of the Common Stock; (ii) to determine the exercise price per share of Options to be granted, which exercise price shall be determined in accordance with Section 9(a) of the Plan; (iii) to interpret the Plan; (iv) to prescribe, amend and rescind rules and regulations relating to the Plan; (v) to authorize any person to execute on behalf of the Company any instrument required to effectuate the grant of an Award previously granted hereunder; (vi) to make discretionary grants of Options, Restricted Stock and Restricted Stock Units and to determine the terms and conditions of such Awards, and (vii) to make all other determinations deemed necessary or advisable for the administration of the Plan.

(d)

Effect of Board’s Decision . All decisions, determinations and interpretations of the Board shall be final and binding on all Participants and any other holders of any Awards granted under the Plan.

(e)

Suspension or Termination of Option . If the President or his or her designee reasonably believes that a Participant has committed an act of misconduct, the President may suspend the Participant’s right to exercise any Option pending a determination by the Board (excluding the Outside Director accused of such misconduct). If the Board (excluding the Outside Director accused of such misconduct) determines a Participant has committed an act of embezzlement, fraud, dishonesty, nonpayment of an obligation owed to the Company, breach of fiduciary duty or deliberate disregard of the Company rules resulting in loss, damage or injury to the Company, or if a Participant makes an unauthorized disclosure of any Company trade secret or confidential information, engages in any conduct constituting unfair competition, induces any Company customer to breach a contract with the Company or induces any principal for whom the Company acts as agent to terminate such agency relationship, neither the Participant nor his or her estate shall be entitled to exercise any Option whatsoever. In making such determination, the Board (excluding the Outside Director accused of such misconduct) shall act fairly and shall give the Participant an opportunity to appear and present evidence on Participant’s behalf at a hearing before the Board or a committee of the Board.

(a)

General . No person shall have any discretion to select which Outside Directors shall be granted Awards or to determine the number of Shares to be covered by Awards granted to Outside Directors pursuant to this Section 5. Subject to the limitations set forth in Section 5(g), Outside Directors shall receive automatic grants of Awards pursuant to this Section 5 for the number of Shares set forth below.

(b)

First Option . Each Outside Director shall be automatically granted an Option to purchase 45,000 Shares (the “First Option”) on the date on which such person first becomes an Outside Director, whether through election by the stockholders of the Company or appointment by the Board to fill a vacancy.

(c)

Subsequent Option and Stock Award . Each Outside Director, other than the Chairman of the Board or an Outside Director whose First Option is being granted on the date of the Annual Meeting of the Company’s stockholders, shall be automatically granted (i) an Option to purchase 10,000 Shares (a “Subsequent Option”), and (ii) a Restricted Stock award of 5,000 Shares (a “Subsequent Stock Award”) on the date of the Annual Meeting of the Company’s stockholders in each year of his service. The Subsequent Option granted to the Chairman of the Board under this Section 5(c) shall be an Option to purchase 20,000 Shares, and the Subsequent Stock Award granted to the Chairman of the Board under this Section 5(c) shall be for 10,000 Shares.

(d)

First Committee Service Option . Each Outside Director who is appointed to serve on the Audit Committee, the Compensation Committee, Nominating Committee or another standing committee of the Board designated by the Board as qualifying for such grant, shall each be automatically granted an Option to purchase 2,500 Shares (a “First Committee Service Option”) on the date on which such person first is appointed to serve on such standing committee.

(e)

Subsequent Committee Service Option and Stock Award . On the date of the Annual Meeting of the Company’s stockholders, each Outside Director, other than the Chairman of the Audit Committee, Compensation Committee, Nominating Committee or another so designated standing committee of the Board or an Outside Director whose First Committee Service Option is being granted on the date of the Annual Meeting of the Company’s stockholders, who continues to serve on the Audit Committee, the Compensation Committee, Nominating Committee or another so designated standing committee of the Board, shall be automatically granted (i) an Option to purchase 1,250 Shares (a “Subsequent Committee Service Option”), and (ii) an Award of 625 Shares of Restricted Stock (a “Subsequent Committee Service Stock Award”).

(f)

Committee Chair Service Option and Stock Award . On the date of the Annual Meeting of the Company’s stockholders, each Outside Director who serves as a Chairman of the Audit Committee, Compensation Committee or Nominating Committee or another standing committee of the Board designated by the Board as qualifying for such grant, shall be automatically granted an Option to purchase Shares (a “Committee Chair Service Option”), and an Award of Restricted Stock (a “Committee Chair Service Stock Award”), for the number of Shares set forth below.

(i)

The Committee Chair Service Option granted to the Audit Committee Chairman shall be an Option to purchase 5,000 Shares, and the Committee Chair Service Option granted to each of the Chairmen of the other eligible Board committees (including the Compensation Committee Chairman and Nominating Committee Chairman) shall be an Option to purchase 2,500 Shares.

(ii)

The number of Shares subject to the Committee Chair Service Stock Award granted to the Audit Committee Chairman shall be 2,500 Shares, and the number of Shares subject to the Committee Chair Service Stock Award granted to each of the Chairmen of the other eligible Board committees (including the Compensation Committee Chairman and Nominating Committee Chairman) shall be 1,250 Shares.

(i)

Notwithstanding the provisions of subsections 5(b), (c), (d), (e) and (f) hereof, in the event that a grant would cause the number of Shares subject to outstanding Awards plus the number of Shares previously issued pursuant to Awards to exceed the Pool, then each such automatic grant shall be for that number of Shares determined by dividing the total number of Shares remaining available for grant by the number of Outside Directors receiving an Award on such date on the automatic grant date. Any further grants shall then be deferred until such time, if any, as additional Shares become available for grant under the Plan through action of the stockholders to increase the number of Shares which may be issued under the Plan or through cancellation or expiration of Awards previously granted hereunder.

(ii)

The terms of each Option granted under this Section 5 shall be as follows:

(1)

the Option shall be exercisable only while the Outside Director remains a Director of the Company, except as set forth in Section 10 hereof.

(2)

the exercise price per Share shall be 100% of the fair market value per Share on the date of grant of the Option, determined in accordance with Section 9 hereof.

(3)

the First Option shall become exercisable in installments cumulatively as to 33 1/3% of the Shares subject to the First Option on each of the first, second and third anniversaries of the date of grant of the First Option; shares subject to a (A) Subsequent Option, (B) First Committee Service Option, (C) Subsequent Committee Service Option, or (D) Committee Chair Service Option, shall be exercisable as to one hundred percent (100%) of the Shares subject to the Option on the date of gran