In re Kubin: Federal Circuit Ignores Principles of Structural Obviousness in Applying 'Obvious to Try' Test

On April 3, 2009, a three-judge panel of the Court of Appeals for the Federal Circuit unanimously affirmed the decision that the Board of Patent Appeals had reached in Ex Parte Kubin, 2007 WL 2070495 (B.P.A.I. May 31, 2007), thereby reinforcing and extending the applicability of the “obvious to try” test in biotechnology patent law practice. In furthering the “obvious to try” standard, however, the Federal Circuit also undermined its own precedent regarding biochemical structural obviousness ' namely, that the nucleotide sequence of a previously unknown DNA sequence encoding a known or partially known polypeptide is non-obvious. Thus, In re Kubin, 2009 WL 877646 (Fed. Cir. April 3, 2009), now appears to be the first case in which a defined biochemical structure was found to be obvious despite the fact that the structure was previously unknown and unpredictable.

In Ex Parte Kubin, the Board determined that a DNA sequence encoding a functionally characterized but unisolated receptor protein (the NAIL protein, which is located on the surface of certain types of immune cells) was obvious under 35 U.S.C. ' 103(a). The patent examiner had rejected Kubin's claims as obvious over a combination of prior art teachings disclosing: 1) the functional characteristics of the NAIL protein on cultured cells, 2) a monoclonal antibody that binds to a portion of the NAIL protein, and 3) a prophetic example of how to isolate NAIL DNA and the protein using conventional cloning and sequencing methodologies. Notably absent from the prior art, however, was any teaching or suggestion of either the amino acid sequence (complete or partial), or any working example of a method by which to obtain the amino acid or DNA sequence of the NAIL protein.

On appeal to the Board, Kubin argued that, based on the Federal Circuit's previous holdings in In re Bell, 991 F.2d 781 (Fed. Cir. 1993), and In re Deuel, 51 F.3d 1552 (Fed. Cir. 1995), the claimed DNA sequence could not be rendered obvious by the mere knowledge of the protein's functional characteristics and a disclosure of general methods for isolating and characterizing the DNA sequence. In Bell and Deuel, the Federal Circuit established a per se rule affirming the patentability of a specific DNA sequence encoding a completely or partially structurally characterized protein, even given that generally applicable methods were available that could be used to isolate DNA sequences starting from the amino acid sequence of the protein encoded thereby. The court held that a lack of structural obviousness (i.e., lack of a structural relationship between a prior art amino acid sequence and the particular DNA sequence being claimed) in Bell and Deuel rendered the particular DNA sequences non-obvious. Nevertheless, the Board in Ex Parte Kubin determined that, despite the lack of structural obviousness (no amino acid sequence had been identified), the DNA sequence encoding the NAIL protein was obvious.

Basing its decision on the Supreme Court's 2007 decision in KSR v. Teleflex, 550 U.S. 398 (2007), the Board noted that “under KSR, it's now apparent 'obvious to try' may be an appropriate test in more situations than we previously contemplated.” The Board concluded that, because a person skilled in the art would have had reason to try to apply available methodologies to isolate NAIL DNA, and such a person would have had a reasonable expectation of success, the “obvious to try” test applied and rendered the NAIL DNA sequence unpatentably obvious under ' 103(a). In affirming the Board's decision, the Federal Circuit agreed that the Supreme Court's holding in KSR unambiguously established that an obviousness inquiry may include an assessment of whether the combination of a claim's constituent elements is “obvious to try.” Furthermore, the Federal Circuit went on to assert that the Supreme Court's KSR decision “actually resurrects this court's [the Federal Circuit's] own wisdom in In re O'Farrell,” 853 F.2d 894 (Fed. Cir. 1988).

Resurrecting O'Farrell

O'Farrell, a case in which the Federal Circuit found second generation method of cloning claims obvious over the inventor's own prior art, delineated two specific classes of cases in which “obvious to try” is erroneously equated with obviousness under ' 103. In the first class of cases, “what would have been 'obvious to try' would have been to vary all parameters or try each of numerous possible choices until one possibly arrived at a successful result, where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful.” In other words, “where a defendant merely throws metaphorical darts at a board filled with combinatorial prior art possibilities, courts should not succumb to hindsight claims of obviousness.” In the second class of O'Farrell's impermissible “obvious to try” situations, “what was 'obvious to try' was to explore a new technology or general approach that seemed to be a promising field of experimentation, where the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it.” In other words, a mere invitation to experiment should not be used to support an obviousness rejection.

The Federal Circuit found that neither of the two situations in which it is inappropriate to apply the “obvious to try” test existed in the O'Farrell case. Consequently, the court applied the test and found the applicant's claims obvious, stating that “all that is required [for obviousness] is a reasonable expectation of success.” Likewise, the court in Kubin found that neither of the O'Farrell exceptions applied and affirmed the Board's finding of obviousness based on the presence of a “reasonable expectation of success” for obtaining the NAIL DNA sequence, which is “all that is required” for obviousness under ' 103.

In its resurrection of O'Farrell, the Federal Circuit neglected to address one major difference between O'Farrell and Kubin ' O'Farrell involved only method claims, whereas Kubin involved claims to a structure (an isolated nucleic acid molecule). The O'Farrell court had no reason to consider principles of structural obviousness, as this issue was irrelevant to method claims. The claims at issue in Kubin, however, were directed to a biochemical structure, and the principles of structural obviousness set down in Bell and Deuel should have been applied to the facts. Had the court taken the Bell/Deuel precedent into consideration, the outcome in Kubin would have been different.

The Potential for a 'Patent Gap'

Applying Bell and Deuel to Kubin would have likely resulted in a finding of non-obviousness regarding the DNA sequence of the NAIL protein, as the lack of even a partial amino acid sequence made structural obviousness impossible. Yet, by casting aside long-standing principles of structural obviousness in favor of the “obvious to try” test, the Federal Circuit not only determined that the DNA sequence of NAIL was obvious, but it also created the potential for a “patent gap” that could effectively halt progress in some areas of biotechnology. If Kubin et al. had known that, despite the lack of any structurally defined precursors in the prior art, their discovery of the NAIL DNA sequence would be determined obvious and therefore unpatentable, would they still have put the time and effort into isolating it? What motivation will future researchers have to continue to discover new genes and proteins, which could further our understanding of health and disease, if their discoveries will be deemed obvious merely because they are “obvious to try”? After all, isn't it “obvious to try” to identify and characterize any gene that plays a role in cancer, alcoholism, cystic fibrosis, and myriad other diseases and disorders? If the purpose of the patent law system is to benefit society by encouraging innovation, replacing the principles of biochemical structural obviousness with the “obvious to try” standard certainly does not advance that goal.

Warren D. Woessner, Ph.D. is a member of this newsletter's Board of Editors and founding shareholder of Schwegman Lundberg & Woessner, P.A. in Minneapolis, where he provides opinions for litigation support and solutions to complex prosecution problems in the areas of pharmaceuticals and biotechnology. He has started a chemical/pharmaceutical/biotechnology blog at http://www.patents4life.com/, sponsored by the firm. Tania A. Shapiro-Barr is an associate at the firm and practices in biomedical technologies. She has an M.D. and a B.S. in medical microbiology and immunology.

On April 3, 2009, a three-judge panel of the Court of Appeals for the Federal Circuit unanimously affirmed the decision that the Board of Patent Appeals had reached in Ex Parte Kubin, 2007 WL 2070495 (B.P.A.I. May 31, 2007), thereby reinforcing and extending the applicability of the “obvious to try” test in biotechnology patent law practice. In furthering the “obvious to try” standard, however, the Federal Circuit also undermined its own precedent regarding biochemical structural obviousness ' namely, that the nucleotide sequence of a previously unknown DNA sequence encoding a known or partially known polypeptide is non-obvious. Thus, In re Kubin, 2009 WL 877646 (Fed. Cir. April 3, 2009), now appears to be the first case in which a defined biochemical structure was found to be obvious despite the fact that the structure was previously unknown and unpredictable.

In Ex Parte Kubin, the Board determined that a DNA sequence encoding a functionally characterized but unisolated receptor protein (the NAIL protein, which is located on the surface of certain types of immune cells) was obvious under 35 U.S.C. ' 103(a). The patent examiner had rejected Kubin's claims as obvious over a combination of prior art teachings disclosing: 1) the functional characteristics of the NAIL protein on cultured cells, 2) a monoclonal antibody that binds to a portion of the NAIL protein, and 3) a prophetic example of how to isolate NAIL DNA and the protein using conventional cloning and sequencing methodologies. Notably absent from the prior art, however, was any teaching or suggestion of either the amino acid sequence (complete or partial), or any working example of a method by which to obtain the amino acid or DNA sequence of the NAIL protein.

On appeal to the Board, Kubin argued that, based on the Federal Circuit's previous holdings in In re Bell, 991 F.2d 781 (Fed. Cir. 1993), and In re Deuel, 51 F.3d 1552 (Fed. Cir. 1995), the claimed DNA sequence could not be rendered obvious by the mere knowledge of the protein's functional characteristics and a disclosure of general methods for isolating and characterizing the DNA sequence. In Bell and Deuel, the Federal Circuit established a per se rule affirming the patentability of a specific DNA sequence encoding a completely or partially structurally characterized protein, even given that generally applicable methods were available that could be used to isolate DNA sequences starting from the amino acid sequence of the protein encoded thereby. The court held that a lack of structural obviousness (i.e., lack of a structural relationship between a prior art amino acid sequence and the particular DNA sequence being claimed) in Bell and Deuel rendered the particular DNA sequences non-obvious. Nevertheless, the Board in Ex Parte Kubin determined that, despite the lack of structural obviousness (no amino acid sequence had been identified), the DNA sequence encoding the NAIL protein was obvious.

Basing its decision on the Supreme Court's 2007 decision in KSR v. Teleflex , 550 U.S. 398 (2007), the Board noted that “under KSR, it's now apparent 'obvious to try' may be an appropriate test in more situations than we previously contemplated.” The Board concluded that, because a person skilled in the art would have had reason to try to apply available methodologies to isolate NAIL DNA, and such a person would have had a reasonable expectation of success, the “obvious to try” test applied and rendered the NAIL DNA sequence unpatentably obvious under ' 103(a). In affirming the Board's decision, the Federal Circuit agreed that the Supreme Court's holding in KSR unambiguously established that an obviousness inquiry may include an assessment of whether the combination of a claim's constituent elements is “obvious to try.” Furthermore, the Federal Circuit went on to assert that the Supreme Court's KSR decision “actually resurrects this court's [the Federal Circuit's] own wisdom in In re O'Farrell,” 853 F.2d 894 (Fed. Cir. 1988).

Resurrecting O'Farrell

O'Farrell, a case in which the Federal Circuit found second generation method of cloning claims obvious over the inventor's own prior art, delineated two specific classes of cases in which “obvious to try” is erroneously equated with obviousness under ' 103. In the first class of cases, “what would have been 'obvious to try' would have been to vary all parameters or try each of numerous possible choices until one possibly arrived at a successful result, where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful.” In other words, “where a defendant merely throws metaphorical darts at a board filled with combinatorial prior art possibilities, courts should not succumb to hindsight claims of obviousness.” In the second class of O'Farrell's impermissible “obvious to try” situations, “what was 'obvious to try' was to explore a new technology or general approach that seemed to be a promising field of experimentation, where the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it.” In other words, a mere invitation to experiment should not be used to support an obviousness rejection.

The Federal Circuit found that neither of the two situations in which it is inappropriate to apply the “obvious to try” test existed in the O'Farrell case. Consequently, the court applied the test and found the applicant's claims obvious, stating that “all that is required [for obviousness] is a reasonable expectation of success.” Likewise, the court in Kubin found that neither of the O'Farrell exceptions applied and affirmed the Board's finding of obviousness based on the presence of a “reasonable expectation of success” for obtaining the NAIL DNA sequence, which is “all that is required” for obviousness under ' 103.

In its resurrection of O'Farrell, the Federal Circuit neglected to address one major difference between O'Farrell and Kubin ' O'Farrell involved only method claims, whereas Kubin involved claims to a structure (an isolated nucleic acid molecule). The O'Farrell court had no reason to consider principles of structural obviousness, as this issue was irrelevant to method claims. The claims at issue in Kubin, however, were directed to a biochemical structure, and the principles of structural obviousness set down in Bell and Deuel should have been applied to the facts. Had the court taken the Bell/Deuel precedent into consideration, the outcome in Kubin would have been different.

The Potential for a 'Patent Gap'

Applying Bell and Deuel to Kubin would have likely resulted in a finding of non-obviousness regarding the DNA sequence of the NAIL protein, as the lack of even a partial amino acid sequence made structural obviousness impossible. Yet, by casting aside long-standing principles of structural obviousness in favor of the “obvious to try” test, the Federal Circuit not only determined that the DNA sequence of NAIL was obvious, but it also created the potential for a “patent gap” that could effectively halt progress in some areas of biotechnology. If Kubin et al. had known that, despite the lack of any structurally defined precursors in the prior art, their discovery of the NAIL DNA sequence would be determined obvious and therefore unpatentable, would they still have put the time and effort into isolating it? What motivation will future researchers have to continue to discover new genes and proteins, which could further our understanding of health and disease, if their discoveries will be deemed obvious merely because they are “obvious to try”? After all, isn't it “obvious to try” to identify and characterize any gene that plays a role in cancer, alcoholism, cystic fibrosis, and myriad other diseases and disorders? If the purpose of the patent law system is to benefit society by encouraging innovation, replacing the principles of biochemical structural obviousness with the “obvious to try” standard certainly does not advance that goal.

Warren D. Woessner, Ph.D. is a member of this newsletter's Board of Editors and founding shareholder of Schwegman Lundberg & Woessner, P.A. in Minneapolis, where he provides opinions for litigation support and solutions to complex prosecution problems in the areas of pharmaceuticals and biotechnology. He has started a chemical/pharmaceutical/biotechnology blog at http://www.patents4life.com/, sponsored by the firm. Tania A. Shapiro-Barr is an associate at the firm and practices in biomedical technologies. She has an M.D. and a B.S. in medical microbiology and immunology.