Opinion ID: 3066527
Heading Depth: 3
Heading Rank: 6

Heading: Festo III

Text: After the Supreme Court remanded Festo to us, we rendered our second en banc decision in the case. Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., Ltd., 344 F.3d 1359 (Fed. Cir. 2003) (“Festo III”). In Festo III, we summarized the three ways in which the Supreme Court stated that the Festo presumption could be rebutted. Id. at 1369. First, the patentee may demonstrate that “the alleged equivalent would have been unforeseeable at the time of the narrowing amendment.” Id. Second, the patentee may demonstrate that “the rationale underlying the narrowing amendment bore no more than a tangential relation to the equivalent in question.” Id. Finally, there may be “‘some other reason’ suggesting that the patentee could not reasonably have been expected to have described the alleged equivalent.” Id. (citing Festo II, 535 U.S. at 740-41).