FORM OF COMMON STOCK AND WARRANT PURCHASE AGREEMENT

The Company desires to sell, and the Investors desire to purchase, shares of the Company’s common stock, par value $0.001 per share (the “Common Stock”).

In connection with entering into this Agreement, the Company shall issue to the Investors certain Stock Purchase Warrants (each, a “Warrant” and collectively, the “Warrants”) pursuant to which the Investors may purchase up to an aggregate of 150,000 additional shares of Common Stock at a price per share of $9.00 per share (as adjusted for any stock dividends paid in common stock, and any combinations, stock splits, recapitalizations and the like each with respect to the Common Stock). The shares of Common Stock issuable upon exercise of the Warrants are collectively referred to herein as the “Warrant Shares.”

The issuance of the Shares (as defined below), the Warrants and Warrant Shares to the Investors have been registered on the Company’s Registration Statement on Form S-3, Registration No. 333-160498, which was declared effective by the Securities and Exchange Commission (the “SEC”) on July 22, 2009 (the “Registration Statement”).

Subject to the terms and conditions of this Agreement, each Investor agrees, severally but not jointly, to purchase at the Closing (as defined below), and the Company agrees to sell and issue to each Investor at the Closing, (i) that number of shares of Common Stock set forth opposite each Investor’s name on Exhibit A hereto and (ii) Warrants exercisable for that number of shares of Common Stock set forth opposite each Investor’s name on Exhibit A hereto. The shares of Common Stock to be sold pursuant to this Agreement are collectively referred to herein as the “Shares,” and the Shares, the Warrants and the Warrant Shares are collectively referred to herein as the “Securities”. The aggregate purchase price of the Securities shall be $3,602,500 (the “Aggregate Purchase Price”). The number of shares of Common Stock to be issued to Investors hereunder is determined by dividing the Aggregate Purchase Price by $6.55.

At the Closing, the Company shall issue a Warrant to each Investor. The Warrants shall be exercisable for up to an aggregate total of 150,000 shares of Common Stock. The Warrants shall be in substantially the form attached hereto as Exhibit B.

Each Investor agrees to indemnify and hold harmless the Company (and each person, if any, who controls the Company within the meaning of Section 15 of the Securities Act of 1933, as amended (the “Securities Act”), or Section 20 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and each officer of the Company who signs the Registration Statement and each director of the Company) from and against losses, claims, damages or liabilities (or actions or proceedings in respect thereof), joint or several, directly or indirectly, based upon or arising out of (i) any failure of the Investors to comply with the covenants and agreements contained in Section 6 hereof of (ii) untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, any prospectus or prospectus supplement filed with the SEC and used in connection with the offering of the Securities or any amendment or supplement thereto, or any omission or alleged omission of a material fact required to be stated in the Registration Statement, any prospectus or prospectus supplement filed with the SEC and used in connection with the offering of the Securities, or any amendment or supplement thereto, required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading if such untrue statement, alleged untrue statement, omission or alleged omission was made in reliance upon and in conformity with written information furnished to the Company by on behalf of the Investors specifically for use in preparation of the Registration Statement, any prospectus or prospectus supplement; provided, however, that the Investors shall not be liable in any such case for (A) any untrue statement, alleged untrue statement, omission or alleged omission in the Registration Statement, any prospectus or prospectus supplement, or other such document which statement is corrected by the Investors and delivered to the Company prior to the sale from which such loss occurred, (B) any untrue statement, alleged untrue statement, omission or alleged omission in any prospectus which is corrected by the Investors in any subsequent prospectus, or supplement or amendment thereto, and delivered to the Company prior to the sale or sales from which a loss or liability arose, or (C) any failure by the Company to fulfill any of its obligations under Section 4.1 hereof.

The provisions of this Section 4 shall survive the termination of this Agreement.

5. REPRESENTATIONS AND ACKNOWLEDGEMENT OF THE COMPANY.

The Company hereby represents, warrants and covenants to the Investors as follows:

Valid Issuance of Securities. The Shares, when issued, sold and delivered in accordance with the terms hereof for the consideration expressed herein, and the Warrant Shares, when issued upon each Investor’s exercise of the Warrant issued to such Investor pursuant to the terms therein, will be duly and validly authorized and issued, fully paid and nonassessable and free of restrictions on transfer other than restrictions on transfer under this Agreement and the Lock-Up Agreement and applicable state and federal securities laws.

No Short Position. Each Investor represents and warrants that, as of the date of this Agreement, it does not have a Short Position in the Company’s Common Stock. Each Investor further covenants and agrees that during the period as of the date hereof and ending one (1) year thereafter, it will not have a Short Position. A “Short Position” shall mean a position resulting from a “short sale” as such transaction is described in Rule 200 of Regulation SHO promulgated under the Exchange Act.

Geron Corporation

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