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“The Aftermath of Festo v. SMC: Is There ‘Some Other Reason’ For Justifying The Third Festo Rebuttal Criterion?”

November 17, 2007 by in General


In this article published in the Chicago-Kent Law Review, Erin Conway describes the importance of technological innovation as one of the driving forces behind the U.S. patent system. The patent laws encourage this innovation and stimulate invention by granting a time-limited right to exclude to those inventors who fulfill the requirements for patent protection. However, these incentives only exist where the patent laws strike an equal balance between requiring patentees to put the public on notice of the boundaries of their patent protection and protecting patentees from pirating copyists seeking to merely avoid the literal language of the patent. Keeping these ideals in mind, the Supreme Court in Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co. (“Festo VIII”) nobly set out to restore balance between the protective and notice functions of the patent laws by clarifying the scope of two important, yet troublesome doctrines of the patent laws—the doctrine of equivalents and prosecution history estoppel. In the end, the Court created a new presumption—and three criterion for rebutting this presumption—for determining when the doctrine of equivalents would apply and when prosecution history estoppel would bar its use. This Note argues that the third rebuttal criterion set out in Festo VIII greatly diminishes the notice function of patents by elevating the doctrine of equivalents above prosecution history estoppel and greatly favoring protecting patentees over providing notice to the public.