Perkins Coie Achieves Complete Sweep Before PTAB for Monolithic Power Systems, Invalidating Six Semiconductor Patents
San Diego, CA (May 6, 2026)—Perkins Coie is pleased to announce the firm has secured a victory for client Monolithic Power Systems, Inc. (MPS) in seven inter partes review (IPR) proceedings before the Patent Trial and Appeal Board (PTAB). Greenthread, LLC (Greenthread) had asserted claims of patent infringement against MPS in the U.S. District Court for the District of Delaware related to six semiconductor structure patents.
The firm successfully challenged those six patents in seven IPR proceedings, with final written decisions issued recently by the PTAB finding all challenged claims unpatentable across all proceedings.
This outcome concludes a series of IPR proceedings in which Perkins Coie demonstrated that the asserted semiconductor patents lacked the novelty required for patent protection. The PTAB's findings invalidate key patents that had been asserted against MPS, clearing the path for the company to continue its innovation and market leadership in semiconductor-based power electronics solutions.
The Perkins Coie team was led by Partner John Esterhay, who argued the IPRs before the PTAB, and included Partner Bing Ai and Associates Cory Owan and Justin Jiang. This result highlights Perkins Coie's capabilities in post-grant proceedings before the PTAB, where the firm has established a track record of successfully challenging patent validity in technically complex disputes across the technology sector.
MPS is a global provider of semiconductor-based power electronics solutions, serving markets across Asia, Europe, and the United States.