eBay, Inc., operates a popular Internet website that allows private sellers to list goods they wish to sell, either through an auction or at a fixed price. Merc Exchange, LLC, holds a number of patents, including a business method patent for an electronic market designed to facilitate the sale of goods between private individuals by establishing a central authority to promote trust among participants. MercExchange sought to license this patent to eBay, as it had previously done with other companies, but the parties failed to reach an agreement. Later, MercExhange sued eBay for patent infringement in a federal district court. A jury found that MercExchange's patent was valid, that eBay had infringed it, and that MercExchange was entitled to an award of damages. Following the jury verdict, the district court denied MercExchange's motion for a permanent injunction to bar eBay from using MercExchange's patented method. Taking the position that an injunction effectively is a mandatory remedy when a defendant is held liable for patent infringement, the U.S. Court of Appeals for the Federal Circuit reversed the denial of the requested injunction.
Was the Federal Circuit correct in taking this position? Is an injunction a mandatory remedy when patent infringement has been established?