Taking up the remand from the Supreme Court, a divided Federal Circuit panel has held true to its prior decision in Teva v. Sandoz – holding once again that the lower court’s claim construction was incorrect and that the asserted claims (Group I) are invalid as indefinite. The majority (led by Judge Moore and joined by Judge Wallach) did give deference to the lower court’s particular fact-finding, but found that the lower court had drawn incorrect conclusions-of-law from the factual bases. Further, the new ‘reasonable certainty’ definiteness requirement under Nautilus made the invalidity holding even easier to justify.
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In Teva, the Supreme Court held that findings-of-fact subsidiary to a claim construction decision should be given deference on appeal. However, the court also noted that most claim construction issues remain questions of law reviewed without deference to the trial court’s findings. These de novo issues include ultimate claim construction outcome, findings regarding intrinsic evidence, and (according to this opinion) the decision on how to apply any subsidiary factual findings in the analysis.
Here, the patent claims include a copolymer “having a molecular weight of about 5 to 9 kilodaltons.” The problem is that polymer chemists have three different ways that molecular weight could be calculated in this context (peak average; number average; and weight average).
Although ostensibly a claim-construction case, the ultimate issue here is actually whether the “molecular weight” term is unduly indefinite under the standards of 35 U.S.C. 112(b). Indefiniteness is considered part of the claim construction analysis and thus is also a question of law. While the case was pending, the Supreme Court decided the important indefiniteness case of Nautilus v. Biosig. In Nautilus, the court lowered-the-bar by making it much easier to find a patent indefinite whenever a claim’s scope lacks “reasonable certainty.”
In addressing the details of this case on remand, the Federal Circuit first noted that there is no express definition of the molecular weight term and that the patentee’s expert had admitted that the term has no “default” meaning even to a person of skill in the art.
The patentee’s expert testified that one of skill in the art would understand that the the calculation should be peak-average molecular weight because it would be more straightforward to calculate peak-average based upon the data presented in Example 1 and Figure 1 of the patent document. The district court relied upon that conclusion in its analysis. On appeal, the Federal Circuit gave deference to the district court’s factual conclusion but noted that the analysis only goes so far and cannot overcome the claim language itself:
A party cannot transform into a factual matter the internal coherence and context assessment of the patent simply by having an expert offer an opinion on it. The internal coherence and context assessment of the patent, and whether it conveys claim meaning with reasonable certainty, are questions of law. The meaning one of skill in the art would attribute to the term molecular weight in light of its use in the claims, the disclosure in the specification, and the discussion of this term in the prosecution history is a question of law. The district court should not defer to Dr. Grant [Teva’s Expert’s] ultimate conclusion about claim meaning in the context of this patent nor do we defer to the district court on this legal question. To the extent that Teva argues that this ultimate determination deserves deference, it is in error. . . .
Even accepting as correct the district court’s factual determinations about .. the transfer of chromatogram data to create Figure 1, these facts do not resolve the ambiguity in the Group I claim about the intended molecular weight measure.
The intrinsic evidence seen by the Federal Circuit here actually came from the prosecution history of a continuation application related to the patent-in-suit. In that later-case, the examiner rejected a claimed “molecular weight” term as indefinite under 112(b) and the applicant at that time responded that the best definition of molecular weight used weight average rather than peak average. The confusion arises now because the patentee is arguing that the proper definition is peak average. In my view, it is really this late-stage change-in-definition that led to the Federal Circuit’s indefiniteness holding.
Writing in dissent, Judge Mayer argued that the expert testimony should be seen as dispositive here and that the Federal Circuit improperly rejected factual expert testimony. Judge Mayer also suggested that the proper course of action when vacating a lower court claim construction is not to find the claim indefinite but instead to remand to consider whether further factual development is needed.
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Of interest, the majority strongly implies that “clear and convincing evidence” is required to hold a claim invalid for indefiniteness:
We hold that claim 1 is invalid for indefiniteness by clear and convincing evidence because read in light of the specification and the prosecution history, the patentee has failed to inform with reasonable certainty those skilled in the art about the scope of the invention. On this record, there is not reasonable certainty that molecular weight should be measured using Mp. This is the legal question—and on this question—we reverse the district court.
Of course, the clear-and-convincing standard is associated with factual conclusions not questions of law and the Federal Circuit here does not appear to have relied upon any factual conclusions for its decision.