Fisch Sigler

Fisch Sigler LLP was an intellectual property litigation boutique known for its focused practice in complex patent disputes, which formally concluded operations on December 31, 2024. During its active period, the firm maintained offices in key legal centers, including New York, NY, and Washington, D.C.. While not a BigLaw firm, it carved out a niche in high-stakes patent matters.

The firm specialized in technology-driven patent litigation. Its work included representing clients in disputes involving flash memory technologies, digital rights management systems, and secure stream buffer technologies, as evidenced by its involvement in cases such as Western Digital Technologies, Inc. et al. v. Viasat, Inc.. The firm's practice description, as reflected in its cases, indicates a focus on sophisticated technological areas.

Fisch Sigler primarily represented plaintiffs in patent infringement actions. The firm's tracked appearance, Western Digital Technologies, Inc. et al. v. Viasat, Inc., shows them acting on the plaintiff's side, seeking to enforce patent rights for operating companies. This suggests a preference for patent assertion on behalf of technology developers and owners.

A notable case for the firm was Western Digital Technologies, Inc. et al. v. Viasat, Inc., filed in the Northern District of California in July 2022. In this litigation, Fisch Sigler, with David B. Fisch as lead counsel, represented Western Digital in a patent infringement dispute concerning flash memory, digital rights management, and secure stream buffer technologies. While the district court case concluded with a voluntary dismissal, related patent validity challenges, such as an inter partes review of a Viasat patent concerning flash memories, continued, with an appeal reaching the Federal Circuit in January 2026. Additionally, Fisch Sigler also engaged in PTAB proceedings, representing patent owners like Largan Precision Co., Ltd. in inter partes reviews.

Key partners who led the firm's patent litigation efforts included David B. Fisch, Jonathan E. Singer, and Kenneth J. Sigler. Other prominent attorneys involved in their IP practice and PTAB work included Joseph F. Edell and Adam A. Allgood. These individuals were central to the firm's strategy and representation in its patent disputes.