Skip to content Dion N. Cominos


San Francisco
315 Pacific Avenue
San Francisco, CA 94111

Los Angeles
633 West Fifth Street
52nd Floor
Los Angeles, CA 90071


J.D., University of California, Hastings College of the Law

  • Twice received the American Jurisprudence award for academic excellence

B.A., University of California, Berkeley


Top Rated Lawyer-AV® Preeminent™,

Best Lawyers in America® distinction in Construction Law (2021-2024) 

Super Lawyers® distinction in Civil Litigation Defense and Business Litigation (2004-2019, 2022-2023)


Firmwide Managing Partner Dion Cominos has been with GRSM since 1987 and has consistently been recognized as an outstanding practitioner by virtually every leading industry publication including Best Lawyers in America©, Martindale-Hubbell (where he has been distinguished as a top-rated, AV Preeminent lawyer) and being named a Super Lawyer® in California for each year of that program’s existence.

Dion specializes in defending businesses and individuals in a wide variety of claims involving commercial disputes and professional liability matters including errors & omissions claims (including accountants, attorneys, financial planners, tax advisors, teachers, architects, engineers, and others).  He has extensive arbitration and trial experience in numerous civil and administrative proceedings in federal districts and state counties throughout California.  His background also encompasses all forms of alternative dispute resolution, including mediations both in California and abroad, where he has served as both a mediator and arbitrator.  Dion has also served as a guest lecturer/instructor at Hastings College of the Law.

In addition to being published in a number of legal journals and periodicals, he has spoken as a guest panelist at annual meetings of such organizations as the American Bar Association, the Association of Defense Counsel, and PLUS.


  • California
  • U.S. District Courts, California
  • U.S. Court of Appeals, Ninth Circuit


Community Involvement

Dion has been actively involved with the San Francisco charitable Foodbank program, and previously served as a member of the Board of Directors for the Legal Aid Society of San Francisco.

Publications & Presentations