Digest of Cadence Pharms. Inc. v. Exela Pharmsci Inc., No. 2014-1184 (Fed. Cir. Mar. 23, 2015) (precedential). On appeal from D. Del. Before Reyna, Linn, and Wallach.

Procedural Posture: Defendant-Appellant Exela appealed the district court’s construction of claim terms and grant of summary judgment of infringement. CAFC affirmed.

  • Claim Construction: The district court correctly construed the term “buffering agent” to mean “[a]n agent that helps the formulation resist change in pH,” but not to require “an effective concentration to resist material change in pH.” Nothing in the intrinsic record warrants adding an additional requirement that the buffering agent appear in sufficient concentration to resist material change in pH.
  • Claim Construction: The district court correctly construed the term “optionally topped with an inert gas . . . and placed in a closed container in which the prevailing pressure is 65,000 Pa maximum” to mean that the vacuum stoppering step is optional. Plaintiff-Appellee Cadence’s disavowal of the vacuum stoppering step as optional during prosecution is not sufficient evidence to depart from the clear specification and claim language. The Patent Office’s acceptance of the final claim language should be granted deference.
  • Doctrine of Equivalents: The district court’s reliance on expert testimony that reversing the order of the preparation of the claimed composition by first adding “an active ingredient susceptible to oxidation” and then adding water afterwards was reasonable. Defendant’s speculation that other differences between its formulation and the claimed formulation may be responsible for stability is insufficient to show clear error. Further, defendant’s reliance on the doctrine of vitiation is misplaced. The doctrine of vitiation—which forbids a finding of infringement under the doctrine of equivalents when such a finding would eliminate a claim limitation—is not an exception to the doctrine of equivalents, but rather is a “legal conclusion of the lack of equivalence based on the evidence presented and the theory of equivalence asserted.” The reversal of steps in the preparation of defendant’s formulation does not vitiate a claim limitation.
  • Obviousness: The district court correctly found that it would not have been obvious to degrade acetaminophen via hydrolysis, and that plaintiff’s formulation, which requires deoxygenation to levels below 2 ppm, was “technical[ly] difficult[].” Such a finding of non-obviousness is supported by the long-felt need, commercial success, and industry praise for plaintiff’s formulation.