The U.S. Court of Appeals for the Federal Circuit, in affirming a jury verdict of infringement and a damages award of close to $74 million, considered a variety of claim construction issues and held, among other things, that the word “an” in one of the claim limitations should be construed to be singular and not plural. TiVo Inc. v. EchoStar Communications, Case No. 06-1574, 2008 U.S. App. LEXIS 2073 (Fed. Cir., Jan. 31, 2008) (Bryson, J).

Less than 10 years ago, TiVo’s time-shifting digital recording technology became a “must have” digital TV accessory and became widely imitated. In 2004, TiVo sued EchoStar, accusing its DVRs of infringing both hardware and software claims. The jury ultimately found literal infringement of both types of claims and awarded TiVo a total of $74 million in damages. The district court issued a permanent injunction against EchoStar; but that injunction was stayed by the Federal Circuit pending appeal.

The appeal involved a plethora of claim construction issues. Digging deep into the district court claim construction rulings, the Federal Circuit affirmed the judgment of infringement of the software claims, but reversed the judgment of infringement for the hardware claims. Since the damages calculation at trial was not predicated on the infringement of particular claims, and because the Court upheld the jury’s verdict that all of the accused devices infringed the software claims, the Court affirmed the damages award and ordered that the stay of the injunction be lifted.

A particularly interesting claim construction issue centered on the “assembles” limitation found in the hardware claims. To support its non-infringement argument, EchoStar argued that “assembles” limitation covers only an assembly of audio and video components into a single, interleaved MPEG stream. It argued that the accused DVRs do not infringe the hardware claims because they do not assemble audio and video components into a single interleaved MPEG stream, but instead assemble the audio and video streams into two separate MPEG streams. TiVo argued that the Echostar DVRs still infringed because the limitation “an MPEG stream” should be interpreted to mean “one or more MPEG streams.”

Citing Baldwin Graphic Sys. v. Siebert, the Federal Circuit noted that as a general rule, the words “a” or “an” in a patent claim carry the meaning of “one or more.” The Court noted, however, that whether “a” or “an” is treated as singular or plural depends heavily on the context of its use. The Court said that the general rules do not apply when the context clearly evidences that the usage is limited only to the singular. In this case, the Court found that the language of the claims and the written description make clear that the singular meaning should apply. The Court reasoned that when read in context of earlier and later claim limitations, it was clear that the patent contemplated a single MPEG stream. The Court also noted that while the open-ended claim term “comprising” is used to refer generally to the limitations of the hardware claims, the “assembles” limitation itself does not contain that term. Rather, the claim language simply refers to the assembly of two components into “an MPEG stream.”