Court Finds Clear & Convincing Invalidity Despite Previous USPTO Review
The USPTO applies the preponderance of the evidence standard in post-grant patent proceedings to assess patentability relative to applied prior art. For at least this reason, it is far easier to demonstrate unpatentability of a patent claim at the USPTO as compared to invalidity in the district court, which applies the clear and convincing evidentiary standard. As pointed out last week, art failing the lower threshold of the USPTO may even result in summary judgment of no invalidity in the district court.
Applying the above logic then, it would seem imprudent to argue invalidity in the district court based upon art explicitly considered, and rejected by the USPTO in a post-grant proceeding. That is, unless you can convince the court that the earlier USPTO proceeding was incompetent.
Continue Reading Court Unimpressed by PTO Review of Prior Art



