Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co.

 
DOCKET NO.
OP. BELOW
SUBJECT
Patent
AUTHOR
Kennedy

Question(s) Presented

1. “Whether every claim-narrowing amendment designed to comply with any provision of the Patent Act—including those provisions not related to prior art—automatically creates prosecution history estoppel regardless of the reason for the amendment.” 2. “Whether the finding of prosecution history estoppel completely bars the application of the doctrine of equivalents.”

Holding

1. “We agree with the Court of Appeals that a narrowing amendment made to satisfy any requirement of the Patent Act may give rise to an estoppel.” 2. “The Court of Appeals held that prosecution history estoppel is a complete bar, and so the narrowed element must be limited to its strict literal terms. Based upon its experience the Court of Appeals decided that the flexible-bar rule is unworkable because it leads to excessive uncertainty and burdens legitimate innovation. For the reasons that follow, we disagree with the decision to adopt the complete bar.”