The Supreme Court today delivered a unanimous opinion in Mayo v. Prometheus. The central question the Court addressed was whether the diagnostic method claims in patents assigned to Prometheus constituted patent-eligible subject matter under 35 U.S.C. § 101. Those claims were directed to a method for determining suitable dosing ranges of drugs used to treat autoimmune diseases. Reversing a decision by the Federal Circuit, the Court found the diagnostic testing method claims were invalid because they represented conventional applications of laws of nature.

BACKGROUND

Section 101 of the Patent Act outlines the scope of patent eligible subject matter: “Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.” However, the Supreme Court has long held that this provision contains an important exception — that “laws of nature, natural phenomena, and abstract ideas” are not patentable. At issue in Mayo was how this exception applies to medical diagnostic testing claims.