Geron Corporation (Nasdaq:GERN) announced today that the Board of Patent Appeals and Interferences of the U.S. Patent Office (“BPAI”) has reversed an earlier decision from the Patent Office reexamination division that had upheld the claims of U.S. Patent Number 7,029,913. The patent, which is assigned to the Wisconsin Alumni Research Foundation ("WARF") and licensed to Geron, covers human embryonic stem cells and is one of three WARF patents which were upheld in earlier reexamination proceedings. The immediate effect of the BPAI decisions is that WARF will have the opportunity to continue examination of the claims of the ‘913 patent at the examination level of the Patent Office.

“This is not a final rejection of the patent claims,” noted David J. Earp, J.D., Ph.D., Geron’s chief patent counsel and senior vice president of business development. “We are confident that WARF will make a strong case in support of the patentability of these claims in continued examination.”

The three WARF patents that have been subject to reexamination proceedings cover the early work at the University of Wisconsin, dating back to the early 1990s, resulting in the first isolation of non-human primate and human embryonic stem cells.

“These pioneering, broad patents were filed at the very beginning of the development of human embryonic stem cell technologies and will expire beginning in 2015,” noted Dr. Earp. “Geron has a broad and deep portfolio of patents covering our embryonic stem cell technologies that will provide protection well beyond the expiration of these early patents. Over the past several years we have focused on developing technologies to enable the scalable manufacturing of cells that are suitable for therapeutic use and our patent portfolio has been built to protect that investment. For example, we hold method patents covering processes used to produce differentiated, functional cells, and composition patents that cover the differentiated cells themselves. Our patent portfolio is substantial today, and it will continue to grow in parallel with our technical development work, providing Geron with long-term protection for our stem cell products.”

As the world leader in the development of human embryonic stem cell–based therapeutics, Geron holds a broad portfolio of intellectual property rights, encompassing Geron-owned patents and patents licensed from leading academic centers. Today, it includes over 40 issued U.S. patents, over 100 patents issued overseas and more than 200 pending applications worldwide. The in-licensed patents include the WARF patents discussed above, additional WARF patents that are not subject to the reexamination proceedings and patents exclusively licensed from the University of California, the University of Oxford, and the Robarts Institute of the University of Western Ontario. Geron has licensed its patented stem cell technologies to companies including GE Healthcare, Corning Life Sciences, Invitrogen (now Life Technologies Corporation), Chemicon (now Millipore Corporation) and StemCell Technologies, Inc.

About Geron

Geron is developing first-in-class biopharmaceuticals for the treatment of cancer and chronic degenerative diseases, including spinal cord injury, heart failure and diabetes. The company is advancing an anti-cancer drug and a cancer vaccine that target the enzyme telomerase through multiple clinical trials in different cancers. For more information, visit www.geron.com.

Use of Forward-Looking Statements

This news release may contain forward-looking statements made pursuant to the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. Investors are cautioned that statements in this press release regarding potential applications of Geron's human embryonic stem cell technologies and intellectual property constitute forward-looking statements that involve risks and uncertainties, including, without limitation, risks inherent in the development and commercialization of potential products, uncertainty of clinical trial results or regulatory approvals or clearances, need for future capital, dependence upon collaborators and maintenance of our intellectual property rights. Actual results may differ materially from the results anticipated in these forward-looking statements. Additional information on potential factors that could affect our results and other risks and uncertainties are detailed from time to time in Geron's periodic reports, including the annual report on Form 10-K for the year ended December 31, 2009.