Shire Development, LLC v. Watson Pharmaceuticals, Inc. 2013-1409 (Fed. Cir. March 28, 2014)

When construing disputed claim terms in a patent infringement case, the claim terms are to be given “their ordinary and customary meaning as understood by one of ordinary skill in the art.” Dow Chem. Co. v. Sumitomo Chem. Co., 257 F.3d 1364, 1372 (Fed. Cir. 2001).  While the court should look to both the specification and the prosecution history when determining the ordinary and customary meaning of a claim term, the Federal Circuit in Shire Development v. Watson Pharmaceuticals reemphasized that statements made during prosecution do not rise to the level of prosecution disclaimer unless the statements amount to unambiguous disavowals of certain meanings of claim terms.

At issue in Shire Development was U.S. Patent No. 6,773,720, which is directed to a controlled- release oral pharmaceutical composition for treating inflammatory bowel diseases.  Claim 1 of the ‘720 Patent recites a controlled-release oral pharmaceutical composition containing 5-amino- salicylic acid as an active ingredient, and comprising (a) an inner lipophilic matrix, (b) an outer hydrophilic matrix, and (c) optionally other excipients, wherein the active ingredient is present in an amount of 80 to 95% by weight of the total composition.  Claim 1 further recites that the active ingredient is dispersed both in the lipophilic matrix and the hydrophilic matrix.

Shire Development owns the ‘720 Patent and sued Watson Pharmaceuticals for infringement. During claim construction, the district court construed several disputed terms, including “inner lipophilic matrix” and “outer hydrophilic matrix.”  According to the district court, the term  “inner lipophilic matrix” means “a matrix including at least one lipophilic excipient, where the matrix is located within one or more substances,” and the term “outer hydrophilic matrix” means “a matrix of at least one hydrophilic excipient, where the matrix is located outside the inner lipophilic matrix.”  The district court relied on the specification when construing the claim terms, but did not rely on statements made by the applicants during the prosecution of the application that matured into the ‘720 Patent.

On appeal, the Federal Circuit agreed with the district court’s finding that no prosecution disclaimer existed because the statements in the prosecution history were not “unambiguous disavowals” of the claim terms at issue.  The court held that while Shire Development characterized the prior art as not having separate matrices, Shire Development never stated that the claimed invention does have separate matrices.  Despite this, the court nevertheless reasoned that the prosecution history was relevant to claim construction, and that the prosecution history, the structure of the claim, the ordinary meaning of the claim terms, and the specification together evidence a claim construction that requires the inner lipophilic matrix to be separate from the outer hydrophilic matrix.  Thus, while the prosecution history alone was not sufficient evidence to construe the two claimed matrices as separate, the combination of the prosecution history and the other factors compels such an interpretation.

Accordingly, the Federal Circuit held that the claim terms should be construed such that they do not depart from the ordinary and customary meaning of the claims, i.e., that the matrices must be “separate.”  Thus, the Federal Circuit reversed the district court’s claim construction and subsequent finding of infringement, and remanded the case for further proceedings consistent with its claim construction.

In prosecuting patent applications, practitioners should take care when raising patentability arguments.  Even if patentability comments are not explicitly directed to claim language, those comments can, nevertheless, be used in construing the claims in a later proceeding.