Stem Cell Patents Upheld

The Patent & Trademark Office has upheld a pair of patents owned by the Wisconsin Alumni Research Foundation that cover the derivation of primate and human embryonic stem cells. This decision comes less than two weeks after PTO upheld another of WARF's key stem cell patents (C&EN, March 3, page 26). The trio of patents is based on work done by University of Wisconsin, Madison, professor James A. Thomson. The patent set came under fire in 2006 when the New York-based Public Patent Foundation and the California-based Foundation for Taxpayer & Consumer Rights questioned their scientific merit. PTO decided to reexamine the patents at that time. "The patent office has conducted a thoughtful and thorough review of all three patents, and we applaud this final decision on our two most important base stem cell patents," WARF Managing Director Carl E. Gulbrandsen said in a statement.