Foreseeability as a Bar to Proof of Patent Infringement

The doctrine of equivalents is a rule of equity adopted more than 150 years ago by the U.S. Supreme Court. Prosecution history estoppel is a rule of equity that controls access to the doctrine. In May 2002, the Court was called upon to revisit the doctrine and the estoppel rule in <i>Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co. Ltd.</i> Ultimately the Court reaffirmed the doctrine and expanded the estoppel rule, but not without inciting heated debate over the Court's rationale &mdash; especially since it included a new and controversial foreseeability test in its analysis for estoppel.

22 minute read May 01, 2003 at 01:48 PM
By
Tim L. Burgess
Foreseeability as a Bar to Proof of Patent Infringement

The doctrine of equivalents is a rule of equity adopted more than 150 years ago by the U.S. Supreme Court. Prosecution history estoppel is a rule of equity that controls access to the doctrine.

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