As the patent and technology communities continue to analyze the U.S. Supreme Court’s recent opinions pulling back on patent scope and challenging legal standards set by the Court of Appeals for the Federal Circuit (CAFC) (the court of sole appellate jurisdiction over patent cases arising in federal district courts), the CAFC on July 7 released the latest assault on patent scope, a three-judge panel decision in the 19-year-old patent case Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co. Ltd., et al.

Festo Corp. initiated its patent-infringement lawsuit in 1988. After a trial on the merits, in 1994, the district court found infringement (Festo I). The court held that while there was no literal infringement by the defendant, SMC Pneumatic Inc.’s (SMC) device, infringement existed under the doctrine of equivalents.