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Judge Stark construes claims relating to liquid acetaminophen.

Judge Stark recently construed a dozen claim terms relating to patented formulations and methods for making liquid acetaminophen. Cadence Pharmaceuticals, Inc. v. Paddock Laboratories Inc., et al., C.A. No. 11-733-LPS (D. Del. Aug. 22, 2012). The following claim terms were construed:

“stable”
“liquid formulation consisting essentially of acetaminophen dispersed in an aqueous medium”
“buffering agent”
“free radical scavenger”
“an isotonizing agent”
“diluted to a concentration of 2 to 50 mg/ml”
“an aqueous solution”
“an injectable aqueous solution”
“while preserving for a prolonged period”
“deoxygenation of the solution by bubbling with at least one inert gas and/or placing under vacuum, until the oxygen content is below 2 ppm”
“optionally the deoxygenation of the solution is completed by addition of an antioxidant”
“and optionally the aforementioned aqueous solution with an active principal is topped with an inert gas atmosphere heavier than air and placed in a closed container in which the prevailing pressure is 65,000 Pa maximum, and the oxygen content of the aqueous solution is below 2 ppm”
With regard to the claim term “stable”, the Court rejected the defendants’ argument that the term is indefinite under 35 U.S.C. § 112, and therefore not amenable to construction. The Court explained, assuming arguendo that it should even consider indefiniteness in claim construction, that “proof of indefiniteness is an ‘exacting standard’ that requires a determination that the claim term is ‘insolubly ambiguous[]’.” Id. at 5 (quoting Halliburton Energy Servs., Inc. v. M-I LLC, 514 F.3d 1244, 1249-50 (Fed. Cir. 2008)). Here, the Court found that the defendants fell short of showing that the term “stable” was so ambiguous as to be incapable fo construction. Id. at 6.


Cadence Pharmaceuticals, Inc. v. Paddock Laboratories Inc., et al., C.A. No. 11-733-LPS (D. Del. Aug. 22, 2…

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