The United States Supreme Court handed down its decision in Commil USA LLC v. Cisco Systems Inc., case number 13-896, and held in a 6-2 decision, that a good-faith belief that a patent is invalid is not available as a defense to a charge of induced infringement. The Supreme Court reversed the Court of Appeals for the Federal Circuit stating that it erred when it created the defense in its decision that vacated a $74 million verdict against Cisco Systems.

The Federal Circuit had held that “[i]t is axiomatic that one cannot infringe an invalid patent,”and therefore, “a good-faith belief of invalidity is evidence that may negate the specific intent to encourage another’s infringement, which is required for induced infringement.” Commil USA, LLC v. Cisco Systems, Inc., 720 F. 3d 1361, 1368 (Fed.Cir. 2013).

According to the majority, a defendant’s good faith belief that a patent is invalid cannot serve as a defense to charges of inducing infringement of the patent because “[t]he scienter element for induced infringement concerns infringement; that is a different issue than validity.”

“Under the Patent Act ... a patent is ‘presumed valid.’ That presumption takes away any need for a plaintiff to prove his patent is valid to bring a claim.”“If belief in invalidity were a defense to induced infringement, the force of that presumption would be lessened to a drastic degree, for a defendant could prevail if he proved he reasonably believed the patent was invalid.”

The Court rationalized that if the patent is proven invalid then no liability attaches. In other words, one can infringe an invalid patent, but it can not be liable for such infringement.

Although the Supreme Court removed a defense to a charge of induced infringement from an accused infringer’s arsenal, the Court rejected an argument made by Commil and the U.S. government that induced infringement only requires knowledge of a patent. Instead, the Court remained steadfast in its 2011 decision Global-Tech Appliances, Inc. v. SEB S.A., and it confirmed that induced infringement requires proof that the defendant knew of the patent in question and knew the induced acts were infringing.

Justice Scalia authored the dissent and was joined by Chief Justice Roberts. The dissent contended that a defendant, who determines in good faith that a patent is invalid, should be free to act without concerns regarding inducement. According to the dissent, “[b]ecause only valid patents can be infringed, anyone with a good-faith belief in a patent’s invalidity necessarily believes the patent cannot be infringed.” “A good-faith belief that a patent is invalid is therefore a defense to induced infringement of that patent.”

The decision is a mixed bag for patent owners. While the decision removes a defense to induced infringement, it reinforces the Court’s Global-Tech decision, which requires that a patent owner prove that an accused inducer knew of the patent and knew that the induced acts would constitute infringement of the asserted patent claims. For inventors, greater care and creativity in patent drafting will be required to protect innovations without requiring proceeding under an induced infringement theory.