A federal appeals court delayed a Patent Trial and Appeals Board review of Allergan’s patents for its dry-eye drug Restasis until after a court hears oral arguments on jurisdictional issues.

The PTAB inter partes review involves several patents for the drug that Allergan transferred to the St. Regis Mohawk tribe, which then asserted its tribal immunity in the proceedings. In February, PTAB rejected this defense and denied Allergan’s motion to dismiss, saying the tribe only had “illusory rights” to the patents.

Allergan and the tribe filed a joint motion in response, arguing the PTAB lacks the jurisdiction to rule on the patents’ validity because the tribe is a sovereign government. PTAB’s final hearing on the issue was scheduled for April 3, but the decision by the U.S. Court of Appeals for the Federal Circuit, pushes it back until one day after oral arguments in the case in June.