Board Finds Metabolite Claim to be Patentable
By Kevin E. Noonan --
The most significant non-decision from the Supreme Court in recent memory is Justice Breyer's dissent over the Court's decision to dismiss its granted certiorari petition (as improvidently granted) in the Laboratory Corp. v. Metabolite Laboratories, Inc. case regarding the patent-eligibility of this claim:
13. A method for detecting a deficiency of cobalamin or folate in warm-blooded animals comprising the steps of: assaying a body fluid for an elevated level of total homocysteine; and correlating an elevated level of total homocysteine in said body fluid with a deficiency of cobalamin or folate.
The bases for the dissenters' objections to the patentability of this claim has been discussed in prior Patent Docs posts (see "The Supreme Court, In re Bilski and the Lingering Question of Labcorp v. Metabolite"). Today, the Board of Patent Appeals and Interferences issued its decision in an appeal from a final rejection of this claim in reexamination, reversing the Examiner's assertion that the claim was unpatentable for obviousness.
The ex parte reexamination, Control No. 90/008,305, of U.S. Patent 4,940,658 was requested on October 23, 2006, and claims 13, 15-17 and 33 were finally rejected for obviousness over the following references:
• Refsum et al., "Radioenzymic Determination of Homocysteine in Plasma and Urine," Clinical Chemistry 34: 624-28 (1985), cited for teaching methods for determining homocysteine levels in plasma by converted total homocysteine to radiolabeled S-adenosylhomocysteine and then quantifying;
• Kass, "Cytochemical Detection of Homocysteine in Pernicious Anemia and in Chronic Erythremic Myelosis," American Journal of Clinical Pathology 67: 53-56 (1977), cited for teaching chemical methods of homocysteine detection in permicious anemia to detect B12 deficiency, but which test showed cross-reactivity with Coenzyme A;
• Wilcken et al., "Homocysteinemia, Ischemic Heart Disease, and the Carrier State for Monocystinuria," Metabolism 32: 363-70 (1983), cited for teaching homocysteine detection in a twin study showing different folate and B12 levels consistently detected from RBCs; and
• Westhyyzen et al., "Plasma amino acids and tissue methionine levels in fruit bats (Rousettus aegyptiacus) with nitrous oxide-induced vitamin B12 deficiency," British Journal of Nutrition 53: 657-62 (1985), cited for showing in correlation between plasma methionine levels and vitamin B12 deficiency.
The Examiner rejected the claims in reexamination for obviousness, citing the Refsum reference as the primary reference (showing a method for detecting plasma homocysteine) combined with the other references showing a correlation with vitamin deficiency. It would have been obvious to combine the teachings of these references, according to the Examiner, "[b]ased on the correlation between the elevated levels of homocysteine (free and/or complexed) in blood and urine samples with deficiency of cobalamin or folate taught by Kass, Wilcken . . . and Westhuyzen."
Saith the Board: We disagree. The panel first stated the principle, enunciated in KSR International Co. v. Teleflex Inc., requiring "some articulated reasoning with some rationale underpinning to support the legal conclusion of obviousness" (550 U.S. 398, 418 (2007)). Here, the Board opined that the claimed invention requires assaying for "total" homocysteine, which comprises four species (homocysteine, homocystine, homocysteine-cysteine disulfides, and protein-homocysteine mixed disulfides), based on specific findings of fact, and correlating elevated levels with folate and/or vitamin B12 deficiency (without discriminating between the two). The panel then distinguished the cited secondary references (which the Examiner used to establish the correlation between elevated homocysteine levels and vitamin deficiency) from the claimed invention. According to the Board, Kass teaches a chemical reaction test that measures not only homocysteine (and not "total" homocysteine) but also Coenzyme A and further distinguishes between B12 and folate deficiency (contrary to the claimed invention). The Board further opined that the ordinarily skilled worker would not have "reasonably" read the Wilcken reference as teaching a correlation between elevated total homocysteine levels and either folate or B12 deficiency, since neither twin was reliably deficient in either folate or B12. The Westhuyzen reference does suggest a correlation between elevated plasma homocysteine and B12 deficiency, the Board conceded, but only detects homocysteine, not total homocysteine, and there is no evidence that the detected increased in homocysteine would "necessarily mean an increase in 'total' homocysteine." In addition to these deficiencies, the Board found that none of the cited references show any correlation between plasma homocysteine levels and folate deficiency.
The Board then held that "[t]he Examiner has failed to provide a sufficient factual basis to support her conclusion of obviousness i.e. that the applied prior art teaches or suggests all of the claim limitations" (phraseology applying -- but not rigidly applying -- the traditional TSM test remaining as one option under KSR and the Patent Office Guidelines for implementing the KSR decision).
This decision cannot be appealed by the third-party requester, and at least with regard to claim 13 provides no basis for appeal by the patentee (since the patentability of this claim was affirmed in unamended fashion by the Board's decision). It is unlikely that this determination would change Justice Breyer's mind, in any event, since he is on record as believing that:
At most, respondents have simply described the natural law at issue in the abstract patent language of a "process." But they cannot avoid the fact that the process is no more than an instruction to read some numbers in light of medical knowledge. Cf. id., at 192 (warning against "allow[ing] a competent draftsman to evade the recognized limitations on the type of subject matter eligible for patent protection"). One might, of course, reduce the "process" to a series of steps, e.g., Step 1: gather data; Step 2: read a number; Step 3: compare the number with the norm; Step 4: act accordingly. But one can reduce any process to a series of steps. The question is what those steps embody. And here, aside from the unpatented test, they embody only the correlation between homocysteine and vitamin deficiency that the researchers uncovered. In my view, that correlation is an unpatentable "natural phenomenon," and I can find nothing in claim 13 that adds anything more of significance.
The Board's decision properly addresses the legal flaw in Justice Breyer's reasoning, as explicated by Judge Rich in In re Bergy: the question of patent eligibility is distinct from whether an invention satisfies the statutory requirement for patentabity. The Board has affirmed that Claim 13 is patentable; perhaps the Supreme Court will use its review of In re Bilski to address the question of whether the claim is also patent-eligible.
Ex parte Competitive Technologies, Inc. (B.P.A.I. 2009)
Panel: Administrative Patent Judges Spiegel, Adams, and Delmendo
Opinion by Administrative Patent Judge Spiegel