United States: Federal Circuit Abandons "Dictionary-First" Rule of Claim Construction

The U.S. Court of Appeals for the Federal Circuit has now issued its long expected en banc decision, touching on most of the issues identified by the Court in its en banc order but expressly declining to address whether it should accord any deference to trial court claim construction rulings. Phillips v. AWH Corp., Case Nos. 03-1269, -1286 (Fed. Cir. July 12, 2005) (en banc) (Bryson, J.) (Mayar, J. dissenting).

The majority opinion provides a useful, going-forward overview of claim construction protocols and canons of construction as well as a clear retreat from the Texas Digital "dictionary-first" approach to claim construction that has permeated many recent cases. The Phillips decision heralds a return to the intrinsic/extrinsic hierarchal evidence approach of Vitronics v. Conceptronic (1996) and the line of cases that followed. In Vitronics, the Federal Circuit set out a hierarchal framework for claim construction in which one starts with the intrinsic evidence, i.e. the claims, the specification and the prosecution history, to interpret the claims. If the meaning of the claim is clear from examining the intrinsic evidence, the inquiry is over. If the meaning is still unclear, one examines the extrinsic evidence, such as dictionaries, the prior art, the testimony of experts and, in rare occasions, the testimony of the inventor.

The Federal Circuit also reemphasized the importance of the specification for construing claims, citing the venerable (1967) Court of Claims case, Autogiro. The Court instructed the specification’s role is not limited to instances where the inventor expressly defines or limits a term in the specification. Rather, it noted the specification is often the single most important claim construction tool and is more helpful than the prosecution history.

Interestingly, while the Federal Circuit stressed both that "[t]he inquiry into how a person of ordinary skill in the art understands a claim term provides an objective baseline from which to begin claim interpretation," it also warned against undue reliance upon expert testimony—particularly, testimony which is conclusory, unsupported or contradicted by the intrinsic evidence. The Court likewise noted that dictionaries, particularly technical dictionaries, are often helpful to understand how a claim term would be construed by one of skill in the art in question. However, the Court warned dictionary definitions should not be overemphasized since dictionaries attempt to aggregate all possible definitions for particular words and applying all definitions not expressly disclaimed will result in unduly broad claims.

The Court also warned that even though there are times claims should be construed to preserve their validity, that maxim is not a "regular component of claim construction" and generally only applies when the scope of the claim is still ambiguous after applying all of the available tools of claim construction.

By declining to rule on the deference issue the Court maintained its present practice of giving no deference to district court claim construction rulings. Indeed, it was this refusal to accord deference to the more fact-like claim construction inquiries that prompted Judges Mayer and Newman to dissent.

Litigants can now expect that future Markman hearings will be far more focused on intrinsic claim construction evidence and far less on what had become the "battle of the dictionary definitions." It is also less likely future Markman rulings will result in breathtakingly broad literal claim scope as compared to cases decided under the Texas Digital "dictionary-first" rule.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.