Does a patent licensee's filing of a declaratory judgment action against a patent holder shift the burden of persuasion from the holder to the licensee — or must the holder still persuade the trier of fact that the licensee infringes the patent?

The Supreme Court held today that the burden stays with the patent holder, despite the fact that it must carry the burden in the less-desirable posture of a defendant. Medtronic, Inc. v. Mirowski Family Ventures, LLC, No. 12-1128 (U.S. Jan. 22, 2014).

The Court also ruled that enough of a patent law dispute existed between Medtronic, the licensee, and Mirowski Family Ventures, the patent holder, that the district court had subject matter jurisdiction and therefore the power to decide the patent issues.

The patent at issue related to implantable cardioverter defibrillator devices, which detect an abnormal heartbeat and stimulate the heart to beat in a normal way.

The unanimous outcome favors infringement defendants. Does it portend more defense-side wins in an IP-heavy Supreme Court docket this Term?