PTAB Did Not Err in Allowing Petitioner to Add Real Party-in-Interest Without Changing Petition’s Filing Date

In Mayne Pharma International Pty. Ltd. v. Merck Sharp & Dohme Corp., No. 2018-1593 (Fed. Cir. June 21, 2019), the Federal Circuit held that the PTAB did not err by allowing Merck to amend its disclosures to identify its parent company as a real party-in-interest without affecting the petition’s filing date.

After Merck filed a petition for IPR challenging Mayne’s patent, Mayne argued, both before and after institution, that Merck’s IPR petition was incomplete and time barred for failing to identify Merck’s parent entity as a real party-in-interest. The PTAB allowed Merck to amend its mandatory notices to include its parent company without affecting the petition’s filing date. In its final written decision, the PTAB rejected Mayne’s time-bar argument as moot and found the challenged claims unpatentable.

On appeal, the Federal Circuit held that the PTAB did not err in finding that the “interests of justice” permitted allowing Merck to amend the identified real parties-in-interest. In reaching this conclusion, the court explained that both Merck and its patent had agreed to be bound by the estoppel effects from the IPR, that the Board was apprised of conflicts relating to Merck and its parent, that Merck did not attempt to conceal its parent’s identity, and that Mayne’s position was not changed by the amendment. The court also referred to the Supreme Court’s Cuozzo decision and other PTAB decisions allowing amendment to find that the PTAB did not err by allowing Merck to add a real party in interest without changing a petition’s filing date.