By Andrew Chung
WASHINGTON (Reuters) - U.S. Supreme Court justices on Monday appeared divided over whether a federal agency's in-house process for challenging patents violates the constitutional rights of patent owners, leaving the fate of a system that has led to a high rate of patent cancellation uncertain.
In one of the most important patent cases to come before the Supreme Court in years, the nine justices heard an hour of arguments in a dispute over the U.S. Patent and Trademark Office's patent review proceeding known as inter partes review (IPR). A decision to strike down the reviews could fundamentally change the way patents disputes are litigated in the United States.
While some of the court's liberal justices voiced support for the process, other justices raised concerns that the government might be able to revoke patents too easily.
The reviews have become a quick and cheap way for companies to try to invalidate patents owned by competitors and others, and have been especially popular with high technology companies such as such as Apple Inc and Samsung Electronics Co Ltd that are common targets of patent infringement suits.
The court is due to rule on the case by the end of June.
(Reporting by Andrew Chung; Editing by Will Dunham)