In a preliminary finding, the U.S. Patent and Trademark Office has determined that three broad patents issued to the University of Wisconsin at Madison on a technique for isolating and maintaining embryonic stem cells were issued in error because the technique wasn’t really new.
In rejecting the patents after re-examining them, the office found that the inventions described in them “would have been obvious to one skilled in the art” at the time the Wisconsin discoveries were made because of prior discoveries, which were known.