Recently, the Federal Circuit evaluated the patent eligibility of computer-implemented process and medical diagnostic claims, relying on the Supreme Court’s guidance set forth in Bilski v. Kappos, 130 S.Ct. 3218 (2010). The Federal Circuit in Research Corp. Techs. v. Microsoft Corp., Appeal No. 2010-1037 (Fed. Cir. Dec. 8, 2010) held that processes relating to digital image halftoning were patent-eligible and not abstract ideas, even where the claims contained algorithms and formulas. In Prometheus Laboratories, Inc. v. Mayo Collaborative Services, No. 2008-1403 (Fed. Cir. 2010), the Federal Circuit held that medical diagnostic claims are not per se unpatentable for claiming natural phenomena.

Patent Eligibility After Bilski

In Research Corp. and Prometheus, the Federal Circuit began its analysis with a return to statutory principles by reciting Sections 100 and 101 of the Patent Act, noting Section 101′s inclusive scope of patentable subject matter. The court also cautioned that “courts ‘should not read into the patent laws limitations and conditions which the legislature has not expressed.’” [Research Corp. Slip Op. at 13, quoting Diamond v. Diehr, 450 U.S. 175 (1981)]. The court nevertheless acknowledged that ? 101 is not unlimited, as Supreme Court precedent provides three specific exceptions to ? 101′s broad patent-eligibility principles: “laws of nature, physical phenomena, and abstract ideas.” Nonetheless, the Court held that “an application of a law of nature or mathematical formula to a known structure or process may well be deserving of patent protection.” [Prometheus, Slip Op. at 12, emphasis in original, citations omitted.] Recognizing that its prior “machine or transformation” test for patent-eligibility was not the sole test for Section 101 compliance, the court refocused the eligibility analysis on the statute noting that ? 101 eligibility should not become a substitute for a patentability analysis regarding prior art, adequate disclosure of the invention or other statutory requirements.

Abstract Idea or Patentable Process?

With those principles in mind, the court in Research Corp. stated that the claimed digital image halftoning invention as a “process” qualifies for patent eligibility under the categorical language of ?? 100 and 101. The claimed process also was not directed to proscribed laws of nature or physical phenomena. The issue, therefore, was whether the claimed process embodied an unpatentable abstract idea.

The court noted that there was nothing abstract in the claimed process because the invention “presents functional and palpable applications in the field of computer technology.” [Research Corp., Slip Op. at 15]. The court also found that the claims were not abstract ideas because several of the claims required physical implementation, such as a printer, a memory or a display device. The presence of algorithms and formulas in some claims also did not “bring this invention even close to abstractness that would override the statutory categories and context” as the claims must be considered as a whole. [Research Corp., Slip Op. at 15]. The court cautioned however, that “a patent that presents a process sufficient to pass the coarse eligibility filter may nonetheless be invalid as indefinite because the invention would ‘not provide sufficient particularity and clarity to inform skilled artisans of the bounds of the claim.’” [Research Corp., Slip Op. at 16, quoting Star Scientific, Inc. v. R.J. Reynolds Tobacco Co., 537 F.3d 1357, 1371 (Fed. Cir. 2008)]. “That same subject matter might also be so conceptual that the written description does not enable a person of ordinary skill in the art to replicate the process.” [Slip Op. at 16-17].

Natural Phenomena or Patentable Method?

In Prometheus, the claims at issue relate to methods of optimizing the therapeutic efficacy of treatment of an immune-mediated gastrointestinal disorder. The specific claims involve administering and determining a drug level in a patient and separately, determining the level of a drug level in the patient, wherein the determined level is indicative of a need to increase or decrease dosing of the drug. The decision arises from the Supreme Court’s vacation and remand of the case to the Federal Circuit for reconsideration in view of Bilski. In its original decision, the Federal Circuit held that the method claims met the “transformation” prong of the machine-or-transformation test because the asserted claims are in effect claims to methods of treatment, which are always transformative when a defined group of drugs is administered to the body to ameliorate the effects of an undesired condition. The Federal Circuit also held that determining metabolite levels without a treatment step are also transformative because the determination of such levels cannot be determined by mere inspection.

The Federal Circuit on remand held that the claims were patent-eligible because the treatment and determining steps each “recite a patent-eligible application of naturally occurring correlations between a metabolite levels and efficacy or toxicity, and thus do not wholly preempt all uses of the recited correlations.” [Prometheus, Slip Op. at 15]. The claims having the steps of administering specific drugs and measuring specific metabolites do not preempt all uses of natural correlations but rather utilize them in a series of specific steps. The court emphasized the purpose of the claims was to treat the human body, which was made clear in the specification and preambles of the asserted claims, and the fact that the treatment relies on natural processes of the human body does not disqualify the administration (treatment) step from patentability.

The Federal Circuit separately addressed the claims that do not recite a treatment or administration step. The court held that the omission of the treatment step does not diminish patentability because the determining step, which is present in each of the asserted claims, is transformative and central to the claimed method. Some form of manipulation of the patient sample was always required so that at the end of the process, “the human blood sample is no longer human blood; human tissue is no longer human tissue.” [Prometheus, Slip Op. at 18]. The “wherein” clause of the claims also was not deemed fatal to patent eligibility because “a subsequent mental step does not, by itself, negate the transformative nature of prior steps.” [Prometheus, Slip Op. at 21].

Antoinette F. Konski is a partner with Foley & Lardner LLP.

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