The Use of the Doctrine of Equivalents to Fix Mistakes a Mistake?

Through empirical research, this article examines whether the patent system of the United States should limit the doctrine of non-textual infringement to obvious after-arising equivalents. Using five decisions from multiple jurisdictions, including the United States, Japan and Great Britain, the article explains the various patent systems and limitations those patent systems face in deciding whether an infringement is an obvious equivalent. The article then discusses the interpretations of patent claims and the policy implications of those interpretations. The article presents the policy argument for patentees to cover the costs associated with patent prosecution because the alternative would be burdensome costs placed on the public. The article then identifies prosecution history estoppel and prior art rejections as limitations that are eliminated by limiting the doctrine of non-textual infringement to obvious after-arising equivalents. It concludes that limitation on the doctrine of equivalents is consistent with the Supreme Court’s established view that the time of infringement is used for measuring equivalency