S. Calvin "Cal" Capshaw, III

S. Calvin "Cal" Capshaw, III is a founding partner of Capshaw DeRieux, L.L.P. in Gladewater, Texas, where his practice focuses on intellectual property litigation. He has extensive experience serving as local counsel in the U.S. District Court for the Eastern District of Texas. Based on past case filings, his patent litigation work has involved a wide range of technologies, including wireless content delivery, mobile applications, telecommunications systems, and video security systems.

The authoritative case list and web-searchable dockets show Mr. Capshaw almost exclusively representing plaintiffs in patent infringement litigation. He frequently acts as local counsel for patent assertion entities in cases filed against large technology companies. A 2026 report on patent litigation intelligence identified him as one of the most active patent attorneys in the nation by case volume for the period between mid-2020 and mid-2025. The provided data tracks one such plaintiff-side appearance in Rare Breed Triggers Inc et al. v. Thomas Carter II et al.

While court filings indicate his cases may involve parallel proceedings at the Patent Trial and Appeal Board, there is no evidence from the available data to suggest Mr. Capshaw has a regular practice appearing before the PTAB himself.

According to his State Bar of Texas profile, Mr. Capshaw earned his J.D. from Baylor University School of Law and was licensed in Texas in 1986. He is admitted to practice before several federal courts, including the Eastern District of Texas and the U.S. Court of Appeals for the Federal Circuit.