PPC Broadband Inc. (defendant) owned a patent relating to coaxial cable connectors. The patent included language stating that a piece of the connector—called a continuity member—would be positioned to reside around an external portion of the connector. Corning Optical Communications, RF (Corning) (plaintiff) filed a petition requesting an inter partes review of the patent. Corning maintained that the claims were invalid as obvious based on the combination of existing patents. During the inter partes proceeding, the Patent Trial and Appeal Board (the board) used a general dictionary to define the term “reside around.” The board determined that “reside around” meant “in the immediate vicinity of.” The board concluded that a combination of the prior patents explained a continuity member that was positioned in the immediate vicinity of an external portion of the connector. The board also stated that because PPC used the word “surrounded” in the preamble of the claim, “reside around” must have a different meaning. The board held that, given these conclusions, the claims at issue were obvious. PPC appealed, arguing that the board’s construction was unreasonably broad in light of the claims and specification of PPC’s patent. PPC argued that the broadest reasonable construction of “reside around” in light of the claims and specification was “encircle or surround.” The appeal was heard by the United States Court of Appeals for the Federal Circuit.