Federal Circuit Affirms that Tribal Immunity Is Not Available for Inter Partes Review

Jul 27, 2018

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Before the hearing, Allergan assigned its patents to the Saint Regis Mohawk Tribe (“the Tribe”). Under the agreement, Allergan received an exclusive grant-back license to the patents. After the assignment, the Tribe moved to terminate the IPRs based on sovereign immunity, citing two PTAB decisions immunizing the Universities of Florida and Minnesota under the 11th Amendment.2The Board denied the Tribe’s motion on various grounds, including that tribal sovereign immunity was not available in an IPR.3

On appeal, the Tribe argued that tribal sovereign immunity should apply in IPRs because they are contested, adjudicative proceedings. In response, Mylan argued, among other things, that IPR is more like an agency enforcement decision, where tribal immunity does not apply. The Federal Circuit acknowledged that IPR is a “hybrid proceeding” with “adjudicatory characteristics,” but ultimately concluded that it was insufficiently adjudicatory to confer sovereign immunity. Four factors drove the Federal Circuit’s conclusion: (1) the Director possesses broad discretion in the decision to institute; (2) the Board may continue review even if the petitioner chooses not to participate; (3) the rules controlling IPRs are substantially different from the Federal Rules of Civil Procedure, and; and (4) IPRs are not necessarily proceedings in which Congress contemplated tribal immunity to apply.

Although the Federal Circuit limited its holding to tribal sovereign immunity, the decision may have broader consequences for entities such as state universities that traditionally enjoy state sovereign immunity in IPRs. Indeed, the Federal Circuit noted the “many parallels” between tribal and state sovereign immunity. Given this language, it would not be surprising to see future challenges to state sovereign immunity in IPRs.

Saint Regis Mohawk Tribe v. Mylan Pharmaceuticals, Inc., Teva Pharmaceuticals USA, Inc., Akorn, Inc., Nos. 2018-1638, 2018-1639, 2018-1640, 2018-1641, 2018-1642, 2018-1643 (Fed. Cir. July 20, 2018)


1  Nos. 2018-1638, 2018-1639, 2018-1640, 2018-1641, 2018-1642, 2018-1643, slip op. (Fed. Cir. Jul. 20, 2018).

2  Reactive Surfaces LTD., LLP, v. Toyota Motor Corp., IPR2016-01914, IPR2017-00572, Paper 36 (PTAB Jul. 13, 2017); Covidien LP v. Univ. of Florida Research Found. Inc., IPR2016-01274, IPR2016-01275, IPR2016-01276, Paper 21 (PTAB Jun. 28, 2016); see also Kiowa Tribe of Okla. v. Mfg. Techs., Inc., 523 U.S. 751, 754 (1998) (“As a matter of federal law, an Indian tribe is subject to suit only where Congress has authorized the suit or the tribe has waived its immunity.”).

3  Mylan Pharmaceuticals Inc. v. Saint Regis Mohawk Tribe, IPR2016-01127-01132, Paper 129 (Feb. 23, 2018).

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