Katherine Cappaert

Katherine Cappaert is a patent litigation partner known for her expertise in complex intellectual property disputes, particularly within a wide array of technology sectors. Drawing on her background as a mechanical engineer, Ms. Cappaert represents clients in patent litigation before U.S. District Courts, Section 337 investigations at the U.S. International Trade Commission (ITC), and appeals to the U.S. Court of Appeals for the Federal Circuit. Her practice encompasses technologies such as solar manufacturing, semiconductors, consumer electronics, smartphones, fiber optics, cloud and distributed computing systems, seismic surveying, subsea oil exploration, and the automotive industry.

Ms. Cappaert actively works both sides of patent disputes, representing both plaintiffs/complainants and defendants/respondents. For instance, she has served as counsel for complainant Broadcom Corporation in ITC investigations and has successfully defended respondents like Leedarson Lighting Co., Ltd. Her experience also includes representing clients such as American Axle in a multi-patent infringement suit involving automotive driveline technology and acting as lead counsel for Panduit in various proceedings against Corning concerning fiber optic equipment, leading to a favorable settlement.

Currently, Ms. Cappaert is a Partner at Steptoe LLP in Washington, D.C. While the provided case data indicates an appearance with Dorsey & Whitney, recent court filings and firm profiles consistently show her affiliation with Steptoe, including her representation of Terumo BCT, Inc. in patent litigation against Haemonetics Corporation, a dispute involving patents related to blood plasma donation systems. She has also represented Terumo BCT, Inc. as counsel in related proceedings.

A significant portion of Ms. Cappaert's practice involves proceedings before the Patent Trial and Appeal Board (PTAB). She has been recognized as one of the "Top 50 Women in PTAB Trials" by the PTAB Bar Association in 2019, 2021, and 2025, underscoring her regular and impactful involvement in inter partes review (IPR) and post-grant review (PGR) challenges. She frequently publishes and speaks on PTAB-related topics, including best practices and strategic considerations for co-pending proceedings. Prior to her legal career, she worked as a mechanical design engineer.