FESTO DOCTRINE

Festo doctrine. Patents. The rule that the voluntary narrowing of a patent claim may give rise to prosecution-history estoppel. Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 304 F.3d 1289 (Fed. Cir. 2003). [Cases: Patents 168(2.2). C.J.S. Patents § 297.]