Invalidity (Burden of Proof)

CREATIVE COMPOUNDs, LLC. .V STARMARK LABORATORIES

• "[W]e now hold that an accused infringer cannot obtain the benefit of the lower burden of proof that prevails in an interference proceeding simply by alleging, as a defense to infringement, that the asserted patent is invalid based upon a co-pending patent unless common claimed subject matter is first identified and an adjudication of priority is sought."