In re Kubin

Brief Fact Summary. Kubin and Goodwin claimed a patent on the isolation and sequencing of DNA molecules encoding a protein known as the Natural Killer Cell Activation Inducing Ligand (NAIL). The Board of Patent Appeals and Interferences (the Board) rejected their claim as obvious, finding that the claim was the product of ordinary skill and commonsense, and not of innovation. Therefore, NAIL cDNA was not patentable because it would have been obvious to isolate it.

Synopsis of Rule of Law. A patent claim will be denied for obviousness where the prior art would lead a person skilled in the art to seek the claimed invention, with every reasonable expectation that using conventional methodologies will lead to success, thereby rendering the claim “obvious to try.â€

Facts. Kubin and Goodwin claimed a patent on the isolation and sequencing of DNA molecules encoding a protein known as the Natural Killer Cell Activation Inducting Ligand (NAIL). NAIL is a specific receptor protein on the cell surface that plays a role in activating Natural Killer (NK) cells. They also claimed the discovery of a binding relationship between NAIL and a protein known as CD48. Therefore, they claimed a genus of isolated polynucleotides encoding a protein that binds CD48 and is at least 80 percent identical to amino acids 22-221 of SEQ ID NO: 2—the disclosed amino acid sequence for the CD48-binding region of NAIL. Their specification also disclose SEQ ID NO: 1, which recited the specific coding sequence of NAIL, and SEQ ID NO: 3, which recited the full NAIL gene. The specification also contemplated variants of NAIL that held the same binding properties. The Board of Patent Appeals and Interferences (the Board) rejected the claims as obvious under 35 U.S.C. § 103, based on the teachings of U.S. Patent No. 5,688,690 (Valiante) and 2 Joseph Sambrook et al., Molecular Cloning: A Laboratory Manual 43-84 (2d ed. 1989) (Sambrook). Valiante disclosed a receptor protein called “p38†that is found on the surface of human NK cells. Valiante taught that the p38 receptor is present on virtually all human NK cells and also disclosed and claimed a monoclonal antibody specific for p38 called “mAB C1.7.†The Board found that Valiante’s p38 protein was the same protein as NAIL. A monoclonal antibody is an antibody that is mass-produced in the laboratory from a single clone and that recognizes only one antigen. Monoclonal antibodies are useful as probes for specifically identifying and targeting a certain kind of cell. Valiante also taught that “[t]he DNA and protein sequences for the receptor p38 may be obtained by resort to conventional methodologies known to one of skill in the art.†Valiante further described a five-step cloning protocol for “isolating and identifying the p38 receptor,†but did not disclose either the amino acid sequence of p38 recognized by mAb C1.7 or the polynucleotide sequence that enclodes p38. Sambrook described methods for molecular cloning in general. The Board found that Kubin and Goodwin used conventional techniques described by Sambrook to isolate and sequence the gene that codes for NAIL, and also found that their claimed DNA sequence was “isolated from a cDNA library . . . using the commercial monoclonal antibody C1.7 . . . disclosed by Valiante.†Regarding SEQ ID NO: 2, the Board found that Valiante’s patent provided a reasonable expectation of success in obtaining a polynucleotide encoding p38, which was within the scope of the Kubin and Goodwin claim. Due to NAIL’s important role in the human immune response, the Board further found that “one of ordinary skill in the art would have recognized the value of isolating NAIL cDNA, and would have been motivated to apply conventional methodologies, such as those disclosed in Sambrook and utilized in Valiante, to do so.†Kubin and Goodwin appealed and the court of appeals granted review.

Issue. Will a patent claim be denied for obviousness where the prior art would lead a person skilled in the art to seek the claimed invention, with every reasonable expectation that using conventional methodologies will lead to success, thereby rendering the claim “obvious to try�

Held.

(Rader, J.) Yes. A patent claim will be denied for obviousness where the prior art would lead a person skilled in the art to seek the claimed invention, with every reasonable expectation that using conventional methodologies will lead to success, thereby rendering the claim “obvious to try.†First, there was sufficient evidence that Kubin and Goodwin used conventional techniques, as taught in Valiante and Sambrook, to isolate the NAIL gene sequence. Their arguments to the contrary are contradicted by their own disclosure to the extent that they disclose that the gene sequence can be derived and isolated by “standard biochemical methods.†Their argument that other prior art, found in Mathew, teaches away from Valiante, also was properly rejected by the Board, since Mathew’s disclosure, in light of Valiante’s teachings regarding the p38 protein and its role in NK cell activation, would have aroused a skilled artisan’s curiosity to isolate the gene coding for p38. In fact, Mathew “exemplifies how the cDNA encoding 2B4, the mouse version of Valiante’s p38, can be isolated and sequenced.†Although this court previously held in In re Deuel, 51 F.3d 1552 (Fed. Cir. 1995) that “knowledge of a protein does not give one a conception of a particular DNA encoding it,†and that “obvious to try†is an inappropriate test for obviousness, these aspects of Deuel were overturned by the United States Supreme Court in KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398 (2007). The Court repudiated as “error†the Deuel restriction on the ability of a skilled artisan to combine elements within the scope of the prior art, ruling that when there is a design need or market pressure to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the options known within his or her technical grasp, and that if this leads to the anticipated success, the fact that a combination was obvious to try might show that it was obvious under § 103. However, this ruling gives rise to two exceptions to the “obvious to try†test. The first is that, where a claimant simply throws metaphorical darts at a board filled with combinatorial prior art possibilities, courts should not succumb to hindsight claims of obviousness. The second is where 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 regarding the particular form of the claimed invention or how to achieve it. In this case, the claimed invention does not come within either of these exceptions. The record shows that the prior art teaches a protein of interest, a motivation to isolate the gene coding for that protein, and illustrative instructions to use a monoclonal antibody specific to the protein for cloning this gene. Therefore, the claimed invention is “the product not of innovation but of ordinary skill and common sense.†In other words, the record shows that a person skilled in the art would have had a resoundingly “reasonable expectation of success†in deriving the claimed invention in light of the teachings of the prior art. In addition, KSR applies not only to the predictable arts, but also to the unpredictable arts, such as biotechnology, which is the art at issue here. One of skill in the advanced art of biotechnology would find Kubin and Goodwin’s claimed “results†profoundly “predictable†given the well-known and reliable nature of the cloning and sequencing techniques in the prior art, as well as the readily knowable and obtainable structure of an identified protein. The ease and predictability of cloning the gene that codes for that protein cannot be ignored as irrelevant to the question of obviousness. “This court cannot, in the face of KSR, cling to formalistic rules for obviousness, customize its legal tests for specific scientific fields in ways that deem entire classes or prior art teachings irrelevant, or discount the significant abilities of artisans of ordinary skill in an advanced area of art.†Although Valiante did not explicitly supply an amino acid sequence for NAIL or a polynucleotide sequence for the NAIL gene, Kubin and Goodwin’s disclosure, which therefore represents a minor advance in the art, cannot be given patent protection because it is an advance without innovation. To give their minor advance such protection would stifle, instead of promote, progress in the useful arts. Their claimed invention was reasonably expected in light of the prior art and “obvious to try.†Affirmed.

Discussion. This important decision for the biotechnology field makes clear that the level of enablement of the prior art is very important to any conclusion of obviousness, and revives the “obvious to try†test. However, it does not hold that an invention that was “obvious to try†is necessarily obvious under Section 103(a). Going forward, as the court itself observes, the question relating to obvious to try situations will be, “when is an invention that was obvious to try nevertheless nonobvious?†(quoting In re O’Farrell, 853 F.2d 894 (Fed. Cir. 1988)). Kubin does not mean that any patent claiming a cDNA is necessarily obvious if the encoded protein was known in the prior art. It simply means that one can no longer presume that the cDNA is never rendered obvious under those circumstances. Rather, the inquiry becomes whether there was any kind of suggestion or motivation to clone the cDNA, and if there was, whether there was a reasonable expectation of success.