The U.S. Supreme Court ruled last week that, to be liable for induced patent infringement, the would-be infringer must have actual knowledge of infringement, and that willful blindness can constitute actual knowledge. In doing so, the Court affirmed an infringement verdict against Pentalpha Enterprises Ltd. and clarified the amount of knowledge necessary to prove induced infringement, which had split the circuit courts for years.

The patent at issue involved cool-touch deep fryers. The Supreme Court affirmed the Federal Circuit’s ruling that fryers made by Pentalpha infringed the patent in suit, but rejected the Federal Circuit standard that only “deliberate indifference” to the risk of infringement was required for induced infringement.

In an opinion written by Justice Samuel Alito, the Supreme Court ruled 8-1 that a party must have actual knowledge of infringement to be found liable for induced patent infringement. While the Supreme Court agreed that the Federal Circuit used the wrong standard, “we nevertheless affirm the judgment of the court of appeals because the evidence in this case was plainly sufficient to support a finding of Pentalpha’s knowledge under the doctrine of willful blindness.”

Long applied in the criminal context, the concept of willful blindness dictates that defendants cannot escape liability by deliberately shielding themselves from evidence that their conduct is unlawful. The Court noted the widespread application of willful blindness in criminal law, and found no reason that it should not apply equally in civil patent cases.

According to the Supreme Court, willful blindness is a more appropriate standard than the deliberate indifference test because it requires active efforts by an inducer to avoid knowing about the infringement. The Court found that Pentalpha willfully blinded itself to its infringing conduct, because the company’s fryers copied all but certain cosmetic features of the plaintiff’s cool-touch deep fryers. In affirming infringement, the Court noted that the “evidence was more than sufficient for a jury to find that Pentalpha subjectively believed there was a high probability that [plaintiff’s] fryer was patented, that Pentalpha took deliberate steps to avoid knowing that fact, and that it therefore willfully blinded itself.”

The case is Global-Tech Appliances Inc. et al. v. SEB SA, case number 10-6, and the patent in suit is U.S. Patent No. 4,995,312.