Arthur W. Harrigan Jr.

Arthur W. Harrigan Jr. — Patent Litigation Practice Summary

Harrigan is a senior Seattle trial lawyer (WSBA #1751, admitted 1971) whose patent work is narrow and confined to serving as Western District of Washington local counsel. His sole tracked patent appearance is Flexiworld Technologies, Inc. v. Amazon.com, Inc. (W.D. Wash., No. 2:21-cv-01055), a software-patent infringement suit in which he appeared on the plaintiff side for Flexiworld alongside out-of-state lead counsel (UniCourt docket; PACER). Web-searchable dockets show similar local-counsel patent appearances in other W.D. Wash. cases, including Uniloc USA, Inc. v. Cisco Systems, Inc. and Microsoft Corp. v. Datel Design and Development, Inc. (PacerMonitor). His broader practice is not patent-focused — directory profiles and media coverage describe a general commercial and complex-litigation practice spanning construction, maritime, aviation, and arbitration matters, with high-profile non-patent work such as representing King County in the arbitration that helped keep the Seattle Mariners in town (MoreLaw; Martindale; Q13 Fox Seattle). No evidence indicates any regular PTAB/IPR practice.

Side preference: Based on tracked data he has appeared only for patent plaintiffs/NPEs (1 plaintiff appearance, 0 defendant), but in a local-counsel capacity rather than as lead patent strategist — docket filings show his firm signing as local counsel while firms such as Desmarais and Nelson Bumgardner drove the substantive work. Given that role, his "side" likely tracks whatever out-of-state lead counsel needs Seattle admission, rather than reflecting an NPE-versus-operating-company positioning.

Firm context: He is a founding partner of Seattle's Harrigan Leyh Farmer & Thomsen LLP, whose lineage traces to Danielson Harrigan Leyh & Tollefson, formed in 1986 by senior litigation partners from a large Seattle firm; he was previously a principal at Lane Powell (MarketScreener; Prabook). The Washington State Bar Association currently lists his license status as Emeritus/Honorary and not eligible to practice, indicating retirement from active practice.

Bar / education: Harvard University (A.B., cum laude); Columbia Law School (LL.B., 1968, cum laude; Columbia Law Review editor); admitted New York 1969 and Washington 1971; Fellow of the American College of Trial Lawyers (Martindale; WSBA directory).