Mayo v. Prometheus

Mayo v. Prometheus
Case name	Mayo v. Prometheus
Citation	566 U.S. 66 (2012)
Court	Supreme Court of the United States
Decided	March 20, 2012
Docket	10-1150
Majority	Stephen Breyer
Concurrence	Antonin Scalia (in part)
Prior	Court of Appeals for the Federal Circuit decision

Mayo v. Prometheus

Mayo v. Prometheus was a 2012 decision by the Supreme Court of the United States that addressed patent eligibility under United States patent law for medical diagnostic methods. The Court invalidated claims asserted by Prometheus Laboratories, Inc., involving correlations between metabolite levels and therapeutic efficacy, prompting responses from stakeholders including United States Patent and Trademark Office, biotechnology firms, and academic institutions. The ruling invoked precedents such as Diamond v. Diehr, Parker v. Flook, and Alice Corp. v. CLS Bank International.

Background

Prometheus Laboratories held patents claiming methods of determining proper dosing of thiopurine drugs used in treating Crohn's disease, ulcerative colitis, and other inflammatory conditions. The patented claims described steps of administering a drug, measuring concentrations of metabolites like 6-thioguanine nucleotide, and deciding to adjust dosage based on observed metabolite levels. Prometheus sued Mayo Collaborative Services for patent infringement; Mayo sought declaratory judgment and invalidity defenses. The case proceeded from the United States District Court for the District of Arizona to the United States Court of Appeals for the Federal Circuit, which affirmed patent validity before the matter reached the Supreme Court of the United States.

Supreme Court Decision

In a unanimous opinion authored by Stephen Breyer, the Court held that the claimed methods were not patent-eligible under 35 U.S.C. § 101 because they effectively claimed a law of nature—the correlation between metabolite levels and therapeutic efficacy—and added only routine, conventional activity. The decision cited earlier rulings such as Diamond v. Chakrabarty for patent-eligible subject matter and Mayo Collaborative Services v. Prometheus Laboratories, Inc. reasoning connected to Bilski v. Kappos jurisprudence. The Court vacated the Federal Circuit's judgment and remanded with instructions to apply the proper patent-eligibility framework.

Legal Reasoning and Tests Applied

The Court applied a two-step framework: first, determine whether the claims are directed to a patent-ineligible concept such as a law of nature or natural phenomenon; second, assess whether claim elements, individually and as an ordered combination, add an "inventive concept" sufficient to transform the nature of the claim into a patent-eligible application. The opinion relied on precedents including Parker v. Flook, Diamond v. Diehr, and later invoked by Alice Corp. v. CLS Bank International to refine patent-eligibility under § 101. The opinion emphasized that routine, conventional steps known in the art—such as administering drugs and using well-understood assays—do not supply the necessary inventive concept. The Court discussed separation-of-powers concerns involving United States Congress authority over patent statutes and referenced the role of the United States Patent and Trademark Office in claim examination.

Impact on Patent Law and Practice

The decision had immediate and profound effects on patent prosecution, litigation strategy, and biotechnology investment. Patent practitioners re-evaluated claim drafting strategies for personalized medicine, diagnostics, and biomarker patents to focus on novel laboratory techniques, engineered compositions, or concrete assay components rather than correlations alone. The ruling influenced examination guidelines at the United States Patent and Trademark Office and informed district court and Federal Circuit analyses in cases involving [precedent] such as Association for Molecular Pathology v. Myriad Genetics, Inc. (though Myriad addressed different issues). Venture capital firms, biotechnology startups, and pharmaceutical companies reassessed patent portfolios and freedom-to-operate analyses; academic medical centers and technology transfer offices adjusted disclosure and claim strategies accordingly.

Subsequent Litigation and Developments

Following the decision, courts applied the Mayo framework in a series of Federal Circuit and district court decisions addressing diagnostic and personalized medicine claims. Subsequent high-profile matters referencing the opinion included disputes over sequencing, biomarker assays, and software-related patents brought to forums such as the United States Court of Appeals for the Federal Circuit and various federal district courts. The decision also intersected with statutory and regulatory developments at the United States Patent and Trademark Office, which issued guidance and memoranda interpreting § 101 in light of Mayo and related Supreme Court rulings. Legislative proposals and hearings in committees of the United States Congress discussed potential reforms to patent eligibility standards.

Academic and Industry Response

Legal scholars at institutions including Harvard Law School, Stanford Law School, Yale Law School, and University of Chicago Law School debated the doctrinal merits and practical consequences, producing articles in journals such as the Harvard Law Review and Yale Journal on Regulation. Biotechnology trade groups and associations like the Biotechnology Innovation Organization and medical societies published commentaries and white papers critiquing the impact on innovation and patient care. Law firms and think tanks hosted symposia examining interactions with policy frameworks from agencies like the National Institutes of Health and the Food and Drug Administration. The consensus in many quarters called for careful claim drafting and potential legislative or administrative clarification to reconcile innovation incentives with constitutional and statutory limits recognized by the Court.

Category:United States Supreme Court cases Category:United States patent case law