The patentee may have gotten away with one here when they failed to provide alternative embodiments in the specification for a broad claim term. It is always good practice to provide multiple examples in the specification for every term you claim more broadly, and perhaps this one wouldn’t have gone all the way up to the CAFC if they had. Another good practice highlighted here that the patentee did well and may have ultimately saved them is to additionally drive home a broad construction via claim differentiation by specifically spelling out alternatives in the claims themselves, along with the specification.
Background / Facts: Interdigital filed a complaint with the ITC against Nokia over patents that focus on controlling transmission power during the “handshake” portion of a wireless cellular communication, which is the portion of the communication in which a cellphone establishes contact with a cellular base station in order to initiate a call. The patents cover a “power ramp-up” strategy that limits the power level of initiation messages sent during the handshake period. When the subscriber unit receives the acknowledgment signal, it fixes the current power level as the designated power level for future communications, thereby empirically establishing the minimum power necessary rather than using an inflated estimation. The ITC ALJ narrowly construed the claim term “code” as restricted to spreading codes and the claim term “continuously,” in relation to increases in the power level, as excluding discrete increases, leading to a finding that Nokia’s system did not infringe the asserted claims.
Issue(s): Whether there is any reason to limit (1) the claim term “code” so as to include only spreading codes and not, for example, scrambling codes, and (2) the claim term “continuously” so as to exclude discrete increases in the power level.
Holding(s): No. The Commission erred in narrowing the plain language of the claim terms “code” and “continuously” increased power levels. (1) The plain language of the term “code” is broad enough to cover both a spreading code and a non-spreading code. Neither the specification nor the prosecution history contains a restrictive definition of “code,” and the patentee did not at any point disavow the broader interpretation of that term. In stark contrast, the court relied heavily on the fact that the “spreading” code limitation was the focus of a dependent claim. The court noted that the doctrine of claim differentiation is at its strongest in this type of case, “where the limitation that is sought to be ‘read into’ an independent claim already appears in a dependent claim.” (2) The use of the term “continuously” does not mandate the interpretation that the power increases must continue even during transmissions. The patents also use the term “continually” to describe the increases in the power level, and that term refers to events that recur intermittently, rather than events that occur without interruption. Because the court concluded that the claim language is broad enough to include both embodiments, the inventors’ failure to include a reference to the alternative embodiment in the specification does not justify excluding that embodiment from the coverage of the claims.