Prometheus Re-bound: Supreme Court Reverses in Mayo v. Prometheus Labs

In a much anticipated decision, a unanimous Supreme Court today reversed the ruling of the Federal Circuit Court of Appeals, and held that Prometheus’ process is not patent eligible. Mayo Collaborative Servs. v. Prometheus Labs., Inc., No. 2008-1403, slip. op. (Fed. Cir. Dec. 17, 2010), rev’d, 566 U.S. __ (2012).

Mayo purchased and used medical diagnostic tests based on Prometheus Labs’ patents, but later sold and marketed its own diagnostic test. Prometheus Labs brought suit, asserting that Mayo’s test kits infringed its patents. The District Court found that while the test kit infringed Prometheus Labs’ patents, the court granted summary judgment that the processes claimed by the patents were not patentable subject matter under 35 U.S.C. § 101, because they claimed natural laws or natural phenomena, specifically, the correlations between thiopurine metabolite levels and the toxicity and efficacy of thiopurine drugs. On appeal, the Federal Circuit reversed, finding the processes to be patent eligible under its “machine or transformation test.” The case was remanded by the Supreme Court for reconsideration in light of Bilski v. Kappos, 561 U.S. __, slip. op. (2010), which sought to clarify the jurisprudence surrounding the “machine or transformation test,” and holding that the latter is not a definitive test of patent eligibility.

In Mayo, the Supreme Court held that the claimed processes have not transformed unpatentable natural laws into patentable applications. As a result, the processes are not patentable and therefore, the claims are invalid. In reaching its decision, the Court looked at the controlling precedents of Parker v. Flook, 437 U.S. 584 (1978) and Diamond v. Diehr, 450 U.S. 175 (1981). In both cases, the Court pointed out that a basic mathematical equation, like a law of nature, was not patentable. In Diehr, the Court held that the process was patent eligible because “of the way the additional steps of the process integrated the equation into the process as a whole.” Mayo, slip op. at 11-12. The process did not suggest that all the steps or a combination of those steps were obvious, already in use or conventional. Id. at 12. In Flook, the process was held not patentable because the claimed process only provided ‘an unpatentable formula for computing an updated alarm limit.’ Id. at 12. The Court then examined the instructions for those who administer doses of thiopure drugs and concluded that the instructions add “nothing specific to the laws of nature other than that is well-understood, routine, conventional activity, previously engaged in by those in the field.” Id. at 13.

Additionally, the Court also looked at other cases, Neilson v. Harford, Webster’s Patent Cases 295, 371 (1841), Bilski v. Kappos, and Gottschalk v. Benson, 409 U.S. 63 (1972), to support its position that appending conventional steps to laws of nature, natural phenomena and abstract ideas does not makes those laws, phenomena and ideas patentable. The Court continued to emphasize its concern that “patent law not inhibit further discovery by improperly tying up the future use of laws of nature.” Mayo, slip op. at 16. Notwithstanding, Prometheus Labs’ arguments to the contrary, the Court declined to change its conclusion that the claimed processes are not patentable. Here, the Court emphasized that its concern relates to “how much future innovation is foreclosed relative to the contribution of the inventor” and noted that “even a narrow law of nature [ ] can inhibit future research.” Id. at 20.

This decision undoubtedly will ripple across many industries, as patent practitioners attempt to apply the holding of the case.