Unsettled Expectations in Patent Law: Festo and the Moving Target of Claim Equivalence (2005)

Description

Kenneth D. Bassinger, Unsettled Expectations in Patent Law: Festo and the Moving Target of Claim Equivalence, 48 How. L.J. 685 (2005)

This article briefly reviews the patent system, including the basics of patent infringement. It discusses the doctrine of equivalents, a common method of asserting patent infringement, paying particular attention to the underlying theories of its application. It then examines prosecution history estoppel, the most prevalent legal theory limiting the doctrine of equivalents. It next analyzes the trilogy of decisions, two by the Federal Circuit and one by the Supreme Court, documenting the rapid pace of change in the legal landscape of prosecution history estoppel. Finally, this Article explores the effect of the sweeping legal changes brought about by the Festo trilogy, concluding that the behavior of patent practitioners will be irretrievably altered to compensate for this dramatic shift in precedent.