GERON CORPORATION 2006 DIRECTORS? STOCK OPTION PLAN

1.

Purposes of the Plan.

2.

Definitions.

(a)

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

(b)

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

(c)

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

(d)

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

(e)

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

(f)

“ Director ” shall mean a member of the Board.

(g)

“ 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.

(h)

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

(i)

“ 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).

(j)

“ Optioned Stock ” shall mean the Common Stock subject to an Option.

(k)

“ Optionee ” shall mean an Outside Director who receives an Option.

(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)

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

(o)

“ Share ” shall mean a share of the Common Stock, as adjusted in accordance with Section 11 of the Plan.

(p)

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

3.

Stock Subject to the Plan.

4.

Administration of and Grants of Options under the Plan.

(a)

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

(b)

Procedure for Grants . All grants of Options hereunder shall be automatic and non-discretionary and shall be made strictly in accordance with the following provisions:

(i)

No person shall have any discretion to select which Outside Directors shall be granted Options or to determine the number of Shares to be covered by Options granted to Outside Directors.

(ii)

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.

(iii)

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 an Option to purchase 20,000 Shares (a “Subsequent Option”) 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 4(b)(iii) shall be an Option to purchase 40,000 Shares.

(iv)

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.

(v)

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 an Option to purchase 2,500 Shares (a “Subsequent Committee Service Option”) on the date of the Annual Meeting of the Company’s stockholders.

(vi)

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”) on the date of the Annual Meeting of the Company’s stockholders. The Committee Chair Service Option granted to the Audit Committee Chairman under this Section 4(b)(vi) shall be an Option to purchase 10,000 Shares. The Committee Chair Service Option granted to the Compensation Committee Chairman and Nominating Committee Chairman under this Section 4(b)(vi) shall each be an Option to purchase 5,000 Shares.

(vii)

Notwithstanding the provisions of subsections (ii), (iii), (iv), (v) and (vi) hereof, in the event that a grant would cause the number of Shares subject to outstanding Options plus the number of Shares previously purchased upon exercise of Options 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 Option 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 shareholders to increase the number of Shares which may be issued under the Plan or through cancellation or expiration of Options previously granted hereunder.

(viii)

The terms of each First Option granted hereunder shall be as follows:

(1)

the First Option shall be exercisable only while the Outside Director remains a Director of the Company, except as set forth in Section 9 hereof.

(2)

the exercise price per Share shall be 100% of the fair market value per Share on the date of grant of the First Option, determined in accordance with Section 8 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.

(ix)

The terms of each Subsequent Option granted hereunder shall be as follows:

(1)

the Subsequent Option shall be exercisable only while the Outside Director remains a Director of the Company, except as set forth in Section 9 hereof.

(2)

the exercise price per Share shall be 100% of the fair market value per Share on the date of grant of the Subsequent Option, determined in accordance with Section 8 hereof.

(3)

the Subsequent Option shall become exercisable as to one hundred percent (100%) of the Shares subject to the Subsequent Option on the date of grant of the Subsequent Option.

(x)

The terms of each First Committee Service Option granted hereunder shall be as follows:

(1)

the First Committee Service Option shall be exercisable only while the Outside Director remains a Director of the Company, except as set forth in Section 9 hereof.

(2)

the exercise price per Share shall be 100% of the fair market value per Share on the date of grant of the First Committee Service Option, determined in accordance with Section 8 hereof.

(3)

the First Committee Service Option shall become exercisable as to one hundred percent (100%) of the Shares subject to the First Committee Service Option on the date of grant of the First Committee Service Option.

(xi)

The terms of each Subsequent Committee Service Option granted hereunder shall be as follows:

(1)

the Subsequent Committee Service Option shall be exercisable only while the Outside Director remains a Director of the Company, except as set forth in Section 9 hereof.

(2)

the exercise price per Share shall be 100% of the fair market value per Share on the date of grant of the Subsequent Committee Service Option, determined in accordance with Section 8 hereof.

(3)

the Subsequent Committee Service Option shall become exercisable as to one hundred percent (100%) of the Shares subject to the Subsequent Committee Service Option on the date of grant of the Subsequent Committee Service Option.

(xii)

The terms of each Committee Chair Service Option granted hereunder shall be as follows:

(1)

the Committee Chair Service Option shall be exercisable only while the Outside Director remains a Director of the Company, except as set forth in Section 9 hereof.

(2)

the exercise price per Share shall be 100% of the fair market value per Share on the date of grant of the Committee Chair Service Option, determined in accordance with Section 8 hereof.

(3)

the Committee Chair Service Option shall become exercisable as to one hundred percent (100%) of the Shares subject to the Committee Chair Service Option on the date of grant of the Committee Chair Service Option.

(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 8(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 8(a) of the Plan; (iii) to interpret the Plan; (iv) to prescribe, amend and rescind rules and regulat