In Saint Regis Mohawk Tribe v. Mylan Pharmaceuticals Inc., Nos. 18-1638 to 18-1643, the Federal Circuit, in a precedential decision, affirmed the PTABs denial of St. Regis’s motion to terminate IPRs filed by Mylan based on tribal sovereign immunity. Tribal immunity does not apply in IPR proceedings because the USPTO is pursuing an adjudicatory agency action.

The Court concluded that “IPR is more like an agency enforcement action than a civil suit brought by a private party…. IPR is more like cases in which an agency chooses whether to institute a proceeding on information supplied by a private party.” Judge Moore writing for the panel majority averred that “[t]he Director’s important role as a gatekeeper and the Board’s authority to proceed in the absence of the parties convinces us that the USPTO is acting as the United States in its role as a superior sovereign to reconsider a prior administrative grant and protect the public interest in keeping patent monopolies ‘within their legitimate scope.'” (quoting Cuozzo Speed Techs., LLC v. Lee, 136 S. Ct. 2131, 2144 (2016)).

In his concurrence, Judge Dyk wrote to describe in greater detail the history of inter partes review proceedings, history that confirms that those proceedings are not adjudications between private parties. While private parties play a role, inter partes reviews are fundamentally an agency reconsideration of the original patent grant, similar to ex parte reexamination and inter partes reexamination proceedings, which are not adjudications of private disputes and to which sovereign immunity does not apply.

The Court’s opinion was limited to whether tribal immunity applies in IPRs: “we leave for another day the question of whether there is any reason to treat state sovereign immunity differently.”