The Federal Circuit, in In re Kubin, Dkt. No. 2008-1184 (Fed. Cir. April 3, 2009), addressed the standards for obviousness after KSR in the biotechnology sector. The Court held that KSR did apply to the unpredictable arts, and found Kubin’s claim to a specific DNA sequence was obvious in light of KSR due to the fact that it was “obvious to try” known methods to obtain that sequence.  

Kubin attempted to claim the DNA sequence encoding a protein he named the NK Cell Activation Inducing Ligand (NAIL). Kubin’s claims were rejected as obvious over prior art that taught the existence of the protein, and a method by which to obtain the claimed DNA sequence encoding NAIL. The prior art in front of the Patent Office during examination contained no purification or isolation of the human NAIL protein, and no NAIL protein sequence or DNA sequence.  

In earlier biotechnology cases, the Federal Circuit held that the mere disclosure of a source of DNA for a protein of interest, in combination with general methods of isolating specific DNAs from that source, cannot render the resulting sequence obvious. See In re Deuel, 51 F.3d 1552 (Fed. Cir. 1995); In re Bell, 991 F.2d 781 (Fed. Cir. 1993). At issue in the Kubin appeal was whether this standard remains intact in light of KSR. (See BPAI appeal decision at 8 (citing KSR Int’l Co. v. Teleflex Inc. , 127 S.Ct. 1727 (2007)).  

In the Kubin decision, the Federal Circuit affirmed the BPAI interpretation of KSR and its impact on Deuel. The Kubin Court concluded that, “Insofar as Deuel implies the obviousness inquiry cannot consider that the combination of the claim’s constituent elements was ‘obvious to try,’ the Supreme Court in KSR unambiguously discredited that holding.” Further, the Court rejected the proposition, set forth by Kubin and BioPharma Amici, that the holding in KSR should be restricted to the predictable arts. The Court concluded that it cannot “customize its legal tests for specific scientific fields in ways that deem entire classes of prior art teachings irrelevant.”  

In declining to apply Deuel to the facts at issue in Kubin, the Federal Circuit cited its opinion in In re O’Farrell to clarify the “obvious to try” standard. According to the Kubin holding, O’Farrell describes circumstances in which “obvious to try” does not constitute obviousness, while KSR firmly establishes the inverse. The Court concluded that the prior art in the Kubin appeal taught a “specific enabling methodology” as required by O’Farrell, and therefore the fact that it was “obvious to try” such a method was in this case sufficient to render the claims obvious.

The question of whether KSR applies to the unpredictable arts has been answered with a “yes” by the holding in Kubin. Obviousness is still, however, a fact intensive inquiry and it is yet to be seen how the availability of an “obvious to try” standard in at least some circumstances will impact the patentability of inventions in the biotechnology and pharmacological sciences. In the wake of Kubin, the question for patent applicants, examiners and the courts will involve assessing where a claim falls on the “obvious to try” spectrum between the circumstances described in KSR, in which “obvious to try” may be synonymous with obviousness, and those set forth in O’Farrell, in which the two terms are not synonymous.