A U.S. patent is “presumed” valid. That means a patent owner does not need to prove the patent is valid in a suit for infringement. And, as the U.S. Supreme Court just explained in Commil United States, LLC v. Cisco Systems, Inc., 2015 U.S. LEXIS 3406 (May 26, 2015), a defendant’s belief that the patent is invalid is not a defense to infringement.
Commil owned a patent that covered a method for increasing the speed of wireless networks. Commil sued Cisco for patent infringement, alleging that Cisco directly infringed the patent by making and using certain network equipment. Commil also alleged that Cisco indirectly infringed the patent by inducing infringement, that is, by selling the equipment to others and instructing them how to use the equipment, causing them to thereby infringe the patent.
At trial, the jury found that Cisco had directly infringed the patent. With respect to the claim of indirect infringement, Cisco contended that it did not have the required specific intent to induce infringement because it believed in good faith that the patent was invalid. The district court for the Eastern District of Texas ruled that Cisco’s evidence of its good faith belief was not admissible as a defense to infringement. The jury found Cisco liable to Commil and awarded Commil $63.7 million in damages.
Cisco appealed to the Federal Circuit Court of Appeals, arguing that the district court’s ruling was erroneous. The appellate court reversed the district court, holding that a good faith belief that a patent is invalid is sufficient to negate the required specific intent to induce infringement.