Nexstep, Inc. v. Comcast Cable Commc’ns, LLC
Authored by: Jeremy J. Gustrowsky
A recent Federal Circuit decision has clarified the high bar for proving patent infringement under the doctrine of equivalents, especially when the technology at issue seems simple. The case involved NexStep, Inc., which accused Comcast Cable Communications, LLC of infringing two patents: U.S. Patent No. 8,885,802 (covering a “digital butler” remote control using Voice over Internet Protocol, or VoIP) and U.S. Patent No. 8,280,009 (covering a “concierge device” that initiates customer support with a single user action).
For the ‘802 patent, the court agreed with the district court’s interpretation that “VoIP” means the capability for two-way voice conversations, not just any audio transmission. Since Comcast’s accused remotes only sent one-way audio commands and didn’t support two-way voice conversations, the court found no infringement. Importantly, the court noted that both parties had agreed “VoIP” was an industry-standard term, and there was no evidence that the patent used the term differently.
The more significant part of the decision addressed the ‘009 patent and the doctrine of equivalents. NexStep argued that even if Comcast’s app required several button presses (rather than a literal “single action”), those steps were equivalent to a single action. However, the Federal Circuit held that to prove infringement under the doctrine of equivalents, a patent owner must provide “particularized testimony and linking argument”—in other words, detailed, specific evidence explaining why the accused product is substantially the same as the claimed invention. The court found NexStep’s expert testimony too vague and conclusory, lacking the necessary explanation of how multiple button presses were equivalent to a single action. The court rejected the idea that a lower standard should apply for “simple” technologies, reaffirming that the doctrine of equivalents always requires detailed, element-by-element proof.
This decision is a reminder that even for seemingly straightforward inventions, patent owners must meet strict evidentiary standards to prove infringement under the doctrine of equivalents. General statements or analogies are not enough—courts require clear, specific explanations that tie the accused product’s features to each element of the patent claim.