Addressing the use of technical dictionaries in claim construction, the U.S. Court of Appeals for the Federal Circuit affirmed a district court’s summary judgment of non-infringement, finding that the district court properly relied on technical dictionaries in its construction of a pivotal term.  Starhome GmbH v. AT&T Mobility LLC, Case No. 12-1694 (Fed. Cir., Feb. 24, 2014) (Schall, J.).

Starhome sued AT&T Mobility alleging infringement of a patent directed to a way of improving the functionality of phone services for users in a roaming network by allowing such users to make calls as if they were in their home networks.  The asserted claims require the use of an “intelligent gateway,” a key term in dispute during claim construction.

The district court determined that the term “gateway” had a well-understood meaning in the art at the time of the invention.  As such, the Court relied on technical dictionaries to construe “gateway” to mean a device that connects two or more networks.  Relying upon this construction, the district court granted summary judgment of non-infringement, as the parties agreed that the accused systems are not connected to multiple networks.  Starhome stipulated to the judgment pending appeal of the construction of the disputed “intelligent gateway” term.

On appeal, Starhome argued that the specification did not require two or more networks, contending that the construction resulted in the exclusion of a disclosed embodiment from the scope of the claim.  The disclosed embodiment depicted the “intelligent gateway” solely in the context of a single network.  The Federal Circuit noted that Starhome’s argument, if true, would carry force because a construction that excludes a preferred embodiment is rarely, if ever, correct.

The Federal Circuit, however, concluded that the alleged embodiment relied upon by Starhome was not, in fact, a separate embodiment because it merely illustrated the flow of a call placed in accordance with another embodiment.  The Court found that the alleged alternate embodiment, at best, inserted ambiguity as to whether or not the patentees intended to depart from the ordinary meaning of “gateway” and that such ambiguity does not rise to the level of clear intent to redefine a claim term, as required by Federal Circuit case law.  The Federal Circuit, therefore, affirmed the lower court’s construction.