WASHINGTON, May 15 (Reuters) - The U.S. Supreme Court set aside on Monday a ruling that an injunction must be imposed on online auctioneer eBay Inc. (EBAY.O: Quote, Profile, Research) in its patent battle with MercExchange, a developer of e-commerce technology.

The justices unanimously set aside the decision by a U.S. appeals court in finding that a permanent injunction barring use of a technology must generally be issued once infringement of a valid patent has been determined.