By Peter Toren (September 28, 2017, 11:56 AM EDT) -- The drug company Allergan PLC has transferred its dry-eye drug Restasis patents to the Saint Regis Mohawk Tribe in upstate New York in an attempt to avoid a challenge to the validity of the patents in an inter partes review before the United States Patent and Trademark Office. Allergan apparently will pay $13.75 million to the tribe in exchange for the tribe claiming sovereign immunity as grounds to dismiss the challenge to the validity of the patents before the USPTO brought by Mylan Pharmaceuticals Inc. The tribe will lease the patents back to Allergan and receive $15 million in annual royalties so long as the patents remain valid. Allergan also is waiting for a decision from a federal district court in the Eastern District on the validity of the same patents, but by transferring the patents to the tribe, the company hopes to avoid having the same issue heard in two venues. Allergan's actions may not be as far-fetched as they appear at first blush: The USPTO has ruled, in a case involving the University of Florida, that challenges to the validity of patents held by the university should be dismissed. As an arm of the state of Florida, the university should be granted sovereign immunity....