A Summary of the Case Prometheus Labs is the exclusive licensee of two patents covering methods for

A Summary of the Case
Prometheus Labs is the exclusive licensee of two patents covering methods for determining patient-specific dosing for thiopurine drugs to treat autoimmune diseases such as Crohn’s disease and ulcerative colitis. The invention was based on the discovery of a correlation between the safety and efficacy of a specific dosage and level of metabolites measured in the blood of a patient.

In 2004, Prometheus Labs filed a patent infringement lawsuit against the Mayo Clinic, alleging that Mayo’s diagnostic test for measuring the metabolism of the thiopurine drugs in the treatment of
autoimmune diseases infringed U.S. Patent Numbers 6,355,623 and 6,680,302. In 2008, the district court granted a summary judgment of invalidity of the two patents because the claimed methods were directed to non-statutory subject matter under 35 U.S.C. §101. The Court of Appeals for the Federal Circuit reversed in 2009, and Mayo filed a petition for a writ of certiorari (a document that a losing party files with the Supreme Court asking it to review the decision of a lower court. It includes a list of the parties, a statement of the facts of the case, the legal questions presented for review, and arguments as to why the Court should grant the writ). The Supreme Court granted certiorari to review the decision, and remanded the case back to the Federal Circuit in light of the Supreme Court’s major 2010 decision regarding patentable subject matter in Bilski v. Kappos. On remand, the Federal Circuit again held on Dec. 17, 2010, that the two patents claimed patentable subject matter because both the “administering” and “determining” steps of the patent claims were transformative, satisfying the machine-or-transformation test set forth in Bilski.

The Supreme Court then granted review of the second Federal Circuit opinion and heard the oral arguments regarding the Prometheus appeal on Dec. 7, 2011. Three months after hearing oral arguments, the Supreme Court issued its landmark decision invalidating the two Prometheus Labs patents on March 20.