After three contentious stem cell patents were upheld in the US earlier this year, the debate over one of the patents continues this week in Europe.

The Board of Appeal at the European Patent Office heard a dispute on Tuesday (June 24) on awarding a patent to the US stem cell technology.

The technology in question is covered by one of the three patents held by the Wisconsin Alumni Research Foundation (WARF). It includes methods to culture and maintain primate embryonic stem cells derived from pre-implantation embryos. This and the other two patents, covering human embryonic stem cells and replicating stem cells in culture, were upheld by the US Patent Office this year.

James Thomson, University of Wisconsin researcher, and chief scientist behind the technology, is challenging the EPO's 2004 decision not to award a patent to this technology. "One of the main reasons for the refusal was that the disclosed method of obtaining stem cells used as the starting material a primate (including human) embryo which was destroyed in the process," the patent office said in a news release last week about the upcoming hearing.

Justin Turner, the lawyer for WARF, told the Board of Appeal that EPO guidelines prevented patenting human embryos themselves, but not the cells derived from them, The Earth Times reported. The board said it would make a ruling before the summer holidays.

Meanwhile, WARF announced today that the US patent office has put the nail in the coffin of the examination process for two of the patents that were upheld by the agency in a final ruling last March. A new reexamination certificate issued by the USPTO on May 29 confirms that the patents, one of which is the one under debate in Europe, cannot be appealed.

The third patent, covering the replication of stem cells in culture, which was upheld separately earlier this year, can still be appealed.



June 26, 2008: This blog has been updated from a previous version.