Federal Circuit hears arguments in In re Kubin; what will be obvious in biotechnology?January 11, 2009

Thursday, the Federal Circuit held oral arguments in In re Kubin, a biotechnology case involving a patent over a gene sequence in humans, and specifically whether the claims were obvious. This was the first precedential decision by the Board of Patent Appeals and Interferences on the issue of obviousness in this field after KSR, so how the Federal Circuit comes out on the issue has the potential to greatly affect examination of biotechnology applications at the USPTO. We previously covered the Board's decision in the case in July. The key issues addressed in oral arguments were whether the prior art, particularly Valiente (a reference teaching a similar protein in mice), rendered the claimed invention obvious, and whether the disclosure of essentially one sequence was sufficient to provide written description for all sequences with 80% similarity that still retain the function of the original gene. Oral argument focused largely on the obviousness issue. Many attended the arguments, including representatives from our office.Click below for more detail of the arguments in In re Kubin.

The three judge panel consisted of judges Rader, Friedman, and Linn. The majority of the court's time was taken in the discussion of the obviousness issue.Neither side debated that Sambrook (commonly known as the Maniatis Manual) merely taught general cloning methods, some of which were applicable to the claims at issue. The core questions were: 1) whether In re Deuel (which held that there must be some teaching to combine Sambrook with another reference before the invention was obvious) was still good law in light of KSR; 2) whether Valiente's claiming a probe which binds to p38 was sufficiently enabling to provide a reasonable expectation of success in cloning and sequencing NAIL (the human p38 homolog); and 3) whether the teaching of Matthews provided motivation to conduct the experimentation or taught away from pursuing a p38 homolog in humans.There are two different tests that could be applied in this case. In re Deuel rejected the "obvious to try" standard, and requires that there be more than a manual teaching common biochemistry techniques to serve as the basis for an obviousness rejection. Instead, the court requires that there be some teaching in the prior art to use the general technique to achieve the desired results. A core question was whether KSR's revival of "obvious to try" as a potentially acceptable ground for an obviousness rejection overruled the Deuel test. If this is the case, then the question would be whether it was obvious to try the standard techniques—a much harder burden for Kubin to bear.The PTO did not argue that Deuel was overruled, instead focusing on the factual differences between Deuel and the present case. Specifically, the PTO argued that in Deuel, the prior art did not teach a particular species of the genus that would be claimed, whereas Valiente actually teaches a probe directed to p38, the mouse homolog to the sequence claimed in the invention. Kubin countered that in Deuel there was a teaching of a partial amino acid sequence which provided more than the prophetic example 12 of Valiente which merely teaches using a probe as part of a standard molecular cloning technique.The teaching of Valiente was a major point of contention. The core issue was prophetic example 12 which teaches the isolation of p39 by use of a NK cell library. Kubin challenged whether this example was enabling by claiming that it did not identify an appropriate starting material, specifically, how to create a human NK cell library expressing NAIL. Kubin specifically noted that it took considerable research to arrive at the appropriate combination of activators (chemicals which activate the expression of a particular gene—in this case NAIL) to achieve an NK cell library with sufficient levels of NAIL to isolate, clone, and sequence the gene. The PTO argued that Valiente provided the entire procedure and that any additional experimentation was merely routine in the art. Kubin countered with the arguments that Valiente failed to teach the active domain (another of the claim limitations) and that the art of NK cell biology is unpredictable. The issue regarding the binding domain led to a discussion as to whether the binding activity was inherent and thus disclosed in Valiente. Kubin's response to the inherency issue was that obviousness requires that the property be inherent and that the inherency be recognized in the art. The reasoning for this was that obviousness is determined from the perspective of one skilled in the art and that unexpected results are considered an indication of nonobviousness. In order to avoid eliminating the possibility of unexpected results, one needs to look at inherency in obviousness from the perspective of one of ordinary skill in the art at the time of the invention, otherwise the unexpected result will necessarily be an inherent property.Based on these positions, a strong question was whether there would be any reasonable expectation of success based on reading Valiente and using the standard techniques set out in Sambrook.Both parties used Matthew in addressing motivation and expectation of success. The PTO characterized Matthew as teaching a successful implementation of Valiente's prophetic example 12 in mouse. The PTO argued that the successful implementation of the example in mouse would motivate one skilled in the art to attempt the procedure with human DNA. Kubin characterized Matthew as a reference which "taught away" from performing the experiment with human DNA. Kubin argued that one skilled in the art would have been dissuaded from trying the experiment with human DNA because the authors of Matthew attempted the experiment and were unable to find any expressed NAIL protein. Kubin argued that one skilled in the art would not be motivated to look for a protein when the art teaches that the protein is not expressed.The PTO instead argued that Matthew was at worst inconsistent because it also taught that there was a conserved DNA sequence similar to p38 in the human genome. Taking this teaching with the teaching of no expression, the PTO characterized the reference as a "challenge to one in the art" to attempt to identify and isolate expressed protein.Given that neither party advocated overturning Deuel, the determination of obviousness in the case appears to turn on whether there is more guidance in the present case than there was in Deuel. This turns on whether Valiente's prophetic example number 12 was sufficiently enabling and which characterization of Matthew is followed by the court.The core issue regarding written description was whether a description of all sequences having 80% similarity to a given sequence while retaining the functionality of the original sequence was sufficient under 35 U.S.C. § 112. Kubin's attorney was questioned as to whether there was actually a sufficient description in the specification to support this claim. Kubin turned to the description of conservative substitutions and argued that this was a "shorthand" way of describing the numerous variants included. The court questioned whether this was consistent with characterizing the art as unpredictable, and the PTO argued that this description did not capture the full scope of the invention.Regarding the predictability and unpredictability of conservative sequence substitution, Kubin characterized this aspect of

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