"Plain Meaning" of Claim Terms Determined Without Extrinsic Evidence

Using the plain and ordinary meaning of the claim terms, the specification and the prosecution history, the U.S. Court of Appeals for the Federal Circuit affirmed-in-part and reversed-in-part the district court’s claim construction, and in doing so broadened the meaning of the disputed term "regularly received television signals." Superguide Corp. v. DirecTV Enterprises, Inc., Case No. 02-1561 (Fed. Cir. Feb. 12, 2004) (Prost, J.) (concurring opinion by Michel, J.)

The district court, relying on the specification of the patent-in-suit, limited the claim term "regularly received television signals" to analog signals. This was based on the explanation in the patent that "when the programming guide is not in use the received television signals are sent directly through the RF section to the television for viewing" and on the fact that only analog signals were broadcast in 1985 (the year the application for the patent was filed). Superguide asserted that the plain meaning of the disputed term covered digital as well.

The Federal Circuit reversed, broadening the disputed term to include digital signals. The majority noted that the district court should not have relied on cases with a means-plus-function claim element to conclude that later developed technology "cannot fall within the literal scope of the [apparatus] claims." According to the majority, claim construction began "by first examining the claim language," which did not limit the disputed term "to any particular type of technology or specify a particular signal format." The Court asserted that "regularly received television signals" refers to "video data" and that "it was known to those skilled in the art during the pendency of the... application that video data could be communicated in either analog or digital format." The majority (quoting SRI Int’l v. Matsushita Elec. Corp. of Am.) noted that the "law ‘does not require that an applicant describe in his specification every conceivable and possible future embodiment of his invention.’" The majority believed that nothing in the prosecution history of the patent had altered the claim construction.

In a concurring opinion, Judge Michel took issue with the construction of the disputed term as encompassing "signals not transmitted by television broadcasters at the time the patent issued." In Judge Michel’s view, the proper inquiry is whether a claim term "would have had a particular meaning to one of ordinary skill in the television art at the time" (emphasis in original) in the context of the overall disclosure, and that the majority erred by considering the term in isolation. Judge Michel noted that the majority did not consider extrinsic evidence such as expert declarations, technical treatises, technical dictionaries, technical publications or contemporaneous or prior art patents to support its meaning of the disputed term. Judge Michel expressed concern "that the use of these ‘short-hand’ expressions about ordinary meaning obscures the correct analysis, tempting panels to look for an ‘ordinary meaning’ divorced from the proper perspective—the artisan’s—and the preferred, proper sources of interpretation—the disclosure, technical dictionaries, prior art patents, and expert testimony."