A “clear and convincing” standard would cause a litigation flood.

The vast explosion in patent litigation began in the mid-1980s, resulting from the reinvigoration of the patent system by Congress, including its establishment of the Court of Appeals for the Federal Circuit. 1 That court, which hears all patent appeals, did what Congress presumably wanted and breathed great strength into patents and their protection. Perhaps too much [*1648] so. So much reinvigoration occurred that patent litigation, once a quiet backwater of the federal courts until the 1980s, has become a swelling sea.

A central reason for the litigation boom is the presumption of validity and the "clear and convincing" standard: Patents are presumed valid under 35 U.S.C. § 282 and can only be set aside in litigation upon "clear and convincing" proof of invalidity. 2 This presumption of validity applies equally to all patents - even those that are almost certainly invalid. This is a huge advantage for the patent holder - and it is often an unfair advantage, given the ease with which applicants and their agents can sneak undeserving claims through the PTO. Because of the burnish of this presumption, patentees can use a weak, arguably invalid patent, to force an accused infringer through years of litigation. This is more than just a nuisiance. Legal defense costs run, at the low end, about three million dollars per case, and range well over ten million dollars in some actions. 3 In the United States, the number of patent infringement suits filed annually nearly doubled between 1994 and 2004. 4 According to the Phoenix Center for Advanced Legal and Economic Public Policy Studies, patent litigation costs the economy 4.5 billion dollars annually. 5

The presumption of validity and the clear and convincing standard would be wise if almost all patents were, in fact, valid. My own experience, however, has been that at least one-third of patent claims asserted in litigation should never have issued. I believe most lawyers, academics, and judges would agree that far too may invalid patents slip through the PTO, even though they would vary up or down from my percentage estimate. 6 But invalid or not, they all receive the forensic advantage of a legal earthwork fortified by a protective moat, namely the presumption of validity in tandem with the clear and convincing standard of proof that is required to overcome that presumption.