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Note: Inter Partes Review: Ensuring Effective Patent Litigation Through Estoppel

By Ann E. Motl. Full text here.

Inter partes review (IPR) is a relatively new proceeding before the Patent and Trademark Office in which a petitioner requests administrative patent judges to review an issued patent and declare its claims invalid. After IPR, the petitioner can continue to litigate patent validity in federal court. However, this second opportunity is tempered by IPR’s estoppel provision, 35 U.S.C. § 315(e). The petitioner is estopped from raising arguments that were raised or reasonably could have been raised. Unfortunately, the estoppel provision is ambiguous.

Federal courts will soon have to choose between a broad estoppel interpretation or a narrower interpretation which would allow more arguments in a subsequent forum. Based on policy and statutory interpretation, courts should interpret the estoppel provision broadly, precluding nearly all arguments the petitioner could have raised in IPR. A broad interpretation of estoppel may make petitioners wary to use IPR, however, and this could thwart Congress’ intent for IPR to be a cost-effective and efficient alternative to federal litigation. This Note thus also proposes procedural changes to the patent litigation system to ensure fairness for both patent owners and patent challengers. Specifically, this Note calls for a prohibition on the administrative patent judges’ denial of redundant arguments in IPR when these arguments meet the necessary standard of institution. This Note also calls for heightened pleading in patent infringement lawsuits to ensure patent challengers are able to draft IPR petitions appropriately. A broad interpretation of estoppel, coupled with these fixes to the patent litigation system, will ensure a better patent litigation system for parties and the courts.