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Regeneron Pharmaceuticals, Inc. v. Merus N.V.
On December 26, 2017, the U.S. Court of Appeals for the Federal Circuit denied a petition for rehearing en banc in this case, which raised important patent-law issues. The denial was a setback for WLF, which filed a brief urging rehearing. A divided Federal Circuit panel struck down a pharmaceutical patent under the “inequitable conduct” doctrine. That doctrine permits invalidation of an otherwise-valid patent if the patentee is alleged to have engaged in inequitable conduct (such as misleading a patent examiner) while seeking issuance of its patent from the Patent and Trademark Office. In a 2011 decision, the Court concluded that assertion of inequitable-conduct claims had gotten out of hand, and it severely limited future application of the doctrine. WLF’s brief argued that the panel’s decision in this case undercuts the 2011 decision and opens the door to unwarranted claims. A silver lining: two judges issued an opinion that dissented from denial of rehearing and cited WLF’s brief.
Case Status:
Rehearing denied.
More Information and Downloads:
9/26/2017: Download the Brief


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