Supreme Court Confirms That Patent Invalidity Must Be Shown By Clear And Convincing Evidence

The Supreme Court last week rejected calls from Microsoft and other technology companies to lower the test for establishing patent invalidity from the current clear and convincing evidence standard to a preponderance of the evidence, particularly when the invalidity challenge rests on evidence not previously considered by the Patent and Trademark Office. In a unanimous decision reaffirming the current heightened standard, the Court declined to consider the parties’ policy arguments and focused instead on Congress’s presumed endorsement of the clear and convincing standard in enacting the Patent Act in 1952. The Court did suggest, however, that juries should be instructed to accord greater weight to evidence not before the PTO in assessing whether an invalidity challenge has met the clear and convincing evidence requirement.