In patent disputes, it's the patent holder—not the accused infringer—who must always bear the burden of proof. That's true even when the parties had struck a licensing deal in the past, the US Supreme Court made clear in a ruling published today.
The case decided was Medtronic, Inc. v. Mirowski Family Ventures. Michel Mirowski and co-inventor Morton Mower were pioneers in the area of implantable heart-stimulation devices (pacemakers). Medtronic paid royalties to Mirowski for some of its products, harking back to its first licensing deal in 1991. But the company said a new generation of devices didn't infringe, and it resisted paying for additional patents Mirowski had acquired in 2003 and 2007.
Mirowski, no surprise, disagreed. The two parties went to court, with Medtronic firing the first shot: a so-called "declaratory judgment" lawsuit saying that it didn't infringe Mirowski's patents.
The situation escalated last year, when the US Court of Appeals for the Federal Circuit, the nation's top patent court, ruled that the burden of proof in that dispute should actually be on Medtronic, not Mirowski, as the lower court had ruled.
Today the Federal Circuit was overruled, in a 9-0 decision written by Justice Stephen Breyer. The burden is always on the patent holder to prove infringement, he explained—even in a situation where in the past, the accused infringer agreed to take a license.
Since patent licensing is so common in the tech sector, the case will have implications beyond the devices at issue. It will generally offer a slight tip of the scales of power, away from companies that want to enforce their patents and in favor of companies that want to challenge those patents.
[link in original] Opinions that short, and unanimous, are rare for the Supreme Court, now or otherwise in history.