The United States Supreme Court was presented with the question of who has the burden of proof when a licensee files an action seeking a declaration of non-infringement against the patentee. In Medtronic Inc. v. Mirowski Family Ventures, 187 L.Ed.2d 703 (Jan. 22, 2014), the Supreme Court reviewed a decision by the Federal Circuit Court, which held that the plaintiff licensee has the burden of proving non-infringement. The Federal Circuit Court, in interpreting the Declaratory Judgment Act, found that Medtronic, as the plaintiff, carried the burden of proof to prove all elements of its claim, as does any other plaintiff. The Supreme Court reversed.
The defendant, Mirowski Family Ventures (“Mirowski”), owned numerous patents relating to implantable heart stimulators. Medtronic entered into a license with Mirowski to practice certain of Mirowski’s patents in exchange for royalties. Pursuant to the terms of the license, Mirowski notified Medtronic of Mirowski’s contention that several of Medtronic’s products violated Mirowski’s patents and, therefore, additional royalties were due. Medtronic disputed the claim, filed an action for declaratory relief, and accrued the disputed unpaid royalties in an escrow account as permitted under the license.