Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes o No x

     Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes o No x

     Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes x No o

     Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes x No o

     Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. x

     Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer”, “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

     The aggregate market value of voting and non-voting common equity held by non-affiliates of the registrant was approximately $508,641,000 based upon the closing price of the common stock on June 30, 2011 on the Nasdaq Global Select Market. Shares of common stock held by each officer, director and holder of five percent or more of the outstanding common stock have been excluded in that such persons may be deemed to be affiliates. This determination of affiliate status is not necessarily a conclusive determination for other purposes.

GERON CORPORATION
FORM 10-K/A

Explanatory Note

     This Amendment No. 1 on Form 10-K/A (the “Amendment”) amends the Annual Report on Form 10-K (the “Original Annual Report”) for the year ended December 31, 2011, which was originally filed with the Securities and Exchange Commission (the “SEC”) on March 7, 2012. We are filing this Amendment in response to a comment letter received from the SEC (the “Comment Letter”) in connection with its review of our confidential treatment request for certain omitted portions of Exhibit 10.36, our office lease agreement with Exponent Realty, LLC, dated February 29, 2012. We have modified Part IV Item 15, “Exhibits, Financial Statement Schedules,” in this Amendment to reflect that confidential treatment for Exhibit 10.36 has been requested and re-filed Exhibit 10.36 in response to the Comment Letter to include Exhibits A – F of the lease agreement and disclose suite numbers, building rentable space, load factor and building percentage. We also have submitted a revised confidential treatment request in response to the Comment Letter. In addition, pursuant to Rule 12b-15 under the Securities Exchange Act of 1934, as amended, new certifications by our principal executive officer and principal financial officer are filed as Exhibits 31.3 and 31.4, respectively, to this Amendment.

     Except as described above, no attempt has been made in this Amendment to modify or update other disclosures presented in the Original Annual Report. This Amendment does not reflect events occurring after the filing of the Original Annual Report or modify or update those disclosures, including the exhibits to the Original Annual Report affected by subsequent events. Accordingly, this Amendment should be read in conjunction with our filings with the SEC subsequent to the filing of the Original Annual Report, including any amendments to those filings.

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PART IV

ITEM 15. EXHIBITS, FINANCIAL STATEMENT SCHEDULES

(a) (1) Consolidated Financial Statements

     See Part II, Item 8 of our Annual Report on Form 10-K for the year ended December 31, 2011, which was originally filed with the SEC on March 7, 2012.

     (2) Financial Statement Schedules

     Financial statement schedules are omitted because they are not required or the information is disclosed in the financial statements listed in Item 15(a)(1) above.

     (3) Exhibits

     See Exhibit Index included herein.

SIGNATURE

     Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this Amendment No. 1 to the Annual Report on Form 10-K/A to be signed on its behalf by the undersigned, thereunto duly authorized.

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EXHIBIT INDEX

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