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PATENT NON-INFRINGEMENT ANALYSIS - Patent Claim Interpretaion by Attorney Timothy B. McCormack

Posted by attorney Timothy Mccormack

PATENT NON-INFRINGEMENT ANALYSIS - Patent Claim Interpretaion by Attorney Timothy B. McCormack

Rule Summary: A finding of patent infringement requires that the accused device or method embody or practice every limitation of at least one claim of the asserted patent. Further, the asserted patent must be valid and enforceable.

Rule Detailed: patent infringement requires an interpretation of the claim (usually does at a Markman hearing) and a comparison of the claim with the accused device or product. Below is a detailed summary of how this works.

A patent has three parts: drawing(s), a written description, and “claims." The “claims" are word descriptions of the subject matter that is covered by the patent. The words of a claim are generally given their ordinary and customary meaning. Phillips v. AWH Corporation, 415 F.3d 1303, 1312-13 (Fed. Cir. 2005).

The ordinary and customary meaning of a claim term “is the meaning that the term would have to a person of ordinary skill in the art in question at the time of the invention." Id. at 1313. This person “is deemed to read the claim term not only in the context of the particular claim in which the disputed term appears, but in the context of the entire patent, including the specification." Id.

Claims do not stand alone. Rather, they are part of a fully integrated written instrument “consisting principally of a specification that concludes with the claims. For that reason, claims must be read in view of the specification, of which they are a part." Phillips, 415 F.3d at 1315 (citing Markman v. Westview Instruments, Inc., 52 F.3d 967, 978-979 (Fed. Cir. 1995) (en banc). The specification usually “is dispositive; it is the single best guide to the meaning of a disputed term." Id., citing Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996).

“The importance of the specification in claim construction derives from its statutory role. The close kinship between the written description and the claims is enforced by the statutory requirement that the specification describe the claimed invention in ‘full, clear, concise, and exact terms.’ 35 U.S.C. § 112, Para. I." Phillips at 1316.

Phillips also stands for the proposition that the specification may define claim terms by implication as well as expressly. In particular, “requiring that any definition of claim language in the specification be express, is inconsistent with our rulings that the specification is ‘the single best guide to the meaning of a disputed term.’" Id at 1320-1321 citing Vitronics at 1582. “Even when guidance is not provided in explicit definitional format, the specification may define claim terms by implication such that the meaning may be found in or ascertained by a reading of the patent documents." Id. at 1321 citing Irdeto Access, Inc. v. Echostar Satellite Corp., 383 F.3d 1295, 1300 (Fed. Cir. 2004).

Claims may also be limited when a common specification in a patent family leads to the “inescapable conclusion" that the claimed inventions must include a structure or an act “in every embodiment even though the claim language was not so limited." Microsoft Corp. v. Multi-Tech Systems, Inc., 357 F.3d 1340, 1348 (Fed. Cir. 2004) (specification of patents led to the “inescapable conclusion" that claims required communications directly over a telephone line, even though the claim language itself was not so limited), citing SciMed Life Systems v. Advanced Cardiovascular Systems. Inc., 242 F.3d 1337, 1342 (Fed. Cir. 2001) (same, specification patents), and Alloc, Inc. v. International Trade Commission, 343 F.3d 1361, 1370 (Fed. Cir. 2003) (same, common specification of patents).

As a matter of both law and common sense, the specification and prosecution history must always be considered as the contextual basis for the claims. Words in isolation often have meanings clarified only by reference to their context. For example, a “magazine" can be a storehouse for explosives, the space in a rifle or pistol from which cartridges are fed, the space in a camera from which rolls of film are fed, or a publication. The meaning of the term can only be sorted out by reference to the context in which the term is used.

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