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Supreme Court Finds Prometheus Patents Unpatentable

Intellectual Property Law Alert John E. Conour, Charles L. Leeck, Gavin J. Milczarek-Desai

The U.S. Supreme Court has unanimously decided that in order for processes applying laws of nature to be patent eligible under 35 U.S.C. § 101, they must also contain an inventive concept (additional elements or a combination of elements) that applies the laws of nature to a new and useful end. Mayo Collaborative Services. v. Prometheus Labs. Inc., 566 U.S. ___ (2012).

The patents in Mayo were directed toward a process for optimizing therapeutic efficacy of the drug, thiopurine, by administering the drug and determining blood levels of the drug metabolite, 6-thioguanine (6-TG). The process further recited that if the levels of 6-TG were below a particular level then more thiopurine should be administered, and if they were too high then less should be administered. Prometheus Laboratories, Inc. was the exclusive licensee of the patents-in-suit, which covered diagnostic tests sold to Mayo Clinic Rochester and Mayo Collaborative Services (Mayo).

In 2004, Mayo indicated its intent to begin making, using and selling its own test with slightly different levels to determine toxicity. Prometheus responded by suing for patent infringement. While the District Court agreed that the Mayo test infringed a claim of the patents-in-suit, it granted summary judgment for Mayo holding that the claimed correlations between thiopurine metabolite levels and toxicity/efficacy of thiopurine are natural laws/ phenomena and not patentable. The Federal Circuit reversed, holding that the patents satisfied the "machine-or-transformation" test because the steps of administering thiopurine and determining the metabolite level involve the transformation of the human body or blood. The Supreme Court granted certiorari, vacated the judgment, and remanded in light of Bilski v. Kappos, 561 U.S. 130 S.Ct. 3218 (2010). The Federal Circuit reaffirmed its previous ruling, and the Supreme Court again granted certiorari.

The Court found Diamond v. Diehr, 450 U. S. 175 (1981) and Parker v. Flook, 437 U. S. 584 (1978) to be the controlling precedents in Mayo, stating that "the claim before us presents a case for patentability that is weaker that the (patent-eligible) claim in Diehr and no stronger than the (unpatentable) claim in Flook. Slip op., at 13. In Diehr, in relevant part, the claimed process, which applied a mathematical equation (not patent-eligible), was held to be patentable due to the way additional steps of the process integrated the equation into the process as a whole. In contrast, the claimed process in Flook employed a mathematical algorithm but failed to further include an "inventive concept" in the application of the algorithm.

In Mayo, the Supreme Court reasoned "if a law of nature is not patentable, then neither is a process reciting a law of nature, unless that process has additional features that provide practical assurance that the process is more than a drafting effort designed to monopolize the law of nature itself." Slip op., at 8-9. The Court indicated that the recited correlations between drug metabolite levels and toxicity/efficacy of the "wherein" step are natural laws. Further, the Court addressed the "additional features" of the "administering" and "determining" steps, indicating that while they are not natural laws, neither are they sufficient to transform the claims to be patent-eligible under § 101. In addressing the "administering" step, the Court highlighted that doctors have administered thiopurine drugs for a long time and reiterated that the "prohibition against patenting abstract ideas 'cannot be circumvented by attempting to limit the use of the formula to a particular technological environment.'" Slip op., at 9, quoting Bilski (slip op., at 14). With regard to the "determining" step, the Court highlighted that the patents disclosed that methods for determining metabolite levels were well known in the art and that "purely conventional or obvious presolution activity is normally not sufficient to transform an unpatentable law of nature into a patent-eligible application of such a law. Slip op., at 10. The Court also noted that considering the steps as an ordered combination was not transformative.

The Supreme Court further addressed the Federal Circuit's application of the "machine-or-transformation" test stating that it cannot supersede the "law of nature" exception to §101: "in stating [that] the 'machine-or-transformation' test is an important and useful clue to patentability, we have neither said nor implied that the test trumps the 'law of nature' exclusion." Slip op., at 19. Of interest, the Court also rejected the government's suggestion that 35 U.S.C. §§ 102, 103, and 112 can perform a "screening function" for patentability in lieu of the "law of nature" exception to § 101.

Therefore, the Supreme Court has not provided a great deal of additional guidance for interpretation of § 101. Rather, the Court has echoed its stance in Diehr, that a process may apply laws of nature; however, the process must also contain an inventive concept embodied by additional elements or a combination of elements, which apply the law of nature in a new and useful way. In light of the Supreme Court's ruling, as a defense to a "law of nature" § 101 rejection, diagnostic and related biotechnical process claim sets should also be accompanied by alternate claim sets that at least tie administration steps to a therapeutic effect (transformation), provide specifics with regard to determination steps, such as incorporating a diagnostic device to be used in the process (machine), or include kit claims.

If you have questions regarding this client alert, please contact John Conour at (312) 715-5168 /, Charles Leeck at (414) 277-5729 /, Gavin Milczarek-Desai at (520) 770-8716 / or your Quarles & Brady attorney.