Before Prost, Reyna and Taranto. Appeal from the U.S. District Court for the Eastern District of Texas

Iridescent sued AT&T and Ericsson for infringement of a patent relating to network communication that provides guaranteed bandwidth, while minimizing data delay and loss. Iridescent argued the claim term “high quality of service connection” means a connection in which at least one of bandwidth, latency, or packet loss are assured from end-to-end. AT&T argued the term was a coined term of degree meaning a connection that assures connection speeds above a certain threshold and packet loss/latency below certain thresholds. The district court agreed with AT&T because the patentee had argued specific thresholds in overcoming a rejection during prosecution. Based on that construction, the parties jointly stipulated to noninfringement. Iridescent appealed claim construction.

The Federal Circuit affirmed. The Federal Circuit agreed that that the term is not sufficiently clear on its face to provide guidance to a person of ordinary skill in the art, and noted that Iridescent relied on certain minimum connection parameters to overcome the examiner’s enablement rejection. Accordingly, the claim term was limited by Iridescent’s arguments made to the examiner to gain allowance of the patent.