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Senior Partner

  • Construction Claims & Disputes
  • Construction Defects-Residential & Commercial
  • Real Estate Litigation & Disputes
  • Landslide & Soils Movement Claims
  • Environmental Claims
  • Inverse Condemnation
  • Mechanics Liens, Stop Notices, Bond Claims
  • Public and Private Construction Projects
  • General Business & Partnership Law
  • Business & Commercial Litigation
  • Complex Civil Litigation Practice
  • Homeowners Association Disputes
  • Arbitration/Mediation Practice
  • Experienced Mediator and Arbitrator


Serge Tomassian is the Firm’s Senior Partner with over 34 years of extensive legal experience.  He has successfully taken to trial and arbitration many complex business, real estate and construction matters. He has also successfully negotiated for his clients in settlement and mediation recoveries in excess of $200 Million. OC Metro Magazine  named Mr. Tomassian as one of Orange County’s Top Real Estate and Construction Lawyers, recognizing his achievements as an experienced & successful litigator and trial lawyer.  He has received the highest rating of “AV” given to Lawyers by the Martindale-Hubble Lawyer Directory, as well as the perfect rating of “10” by AVVO  for both legal ability and professional ethics.  He has been recognized as a “Super Lawyer in Southern California (Thomson Reuters) for the past ten years  and has consistently been named in Best Lawyers in Southern California.  Mr. Tomassian is a member of the State Bar of California and Orange County Bar Association serving for six years on the Board of Directors. He is admitted to practice in the United States Districts Courts, Southern, Central, Eastern and Northern Districts.  Mr. Tomassian served for years as  a Judge Pro Tem and Arbitrator for the Orange County Superior Court.  He currently serves as an Arbitrator and Mediator with the American Arbitration Association.  He was a member of the UOP/McGeorge Law School National Alumni Board of Directors and currently serves on the Dean’s Advisory Council.

Mr. Tomassian’s legal career began as a litigator in the Los Angeles office of the International Law Firm of O’Melveny & Myers.  Since 1993, Mr. Tomassian has been a partner of Tomassian, Inouye & Grigorian LLP and previously related firms. He has served as an expert analyst on  construction and real estate issues and provided analysis to news & media programs. He has been featured and interviewed by several multi-media outlets and publications.  Mr. Tomassian has been a lecturer at legal seminars for lawyers, construction and real estate professionals.  As a Plaintiff’s lawyer, he has successfully obtained many trial verdicts and settlements.  He has also successfully litigated and defended clients against multi-million dollar claims in real estate, construction, entertainment law, employment, and business matters.

He graduated with a BA in Political Science from USC with Phi Beta Kappa Honors and from McGeorge (UOP) School of Law JD, where he was selected to the International Moot Court Honors Bar as Vice President.

Mr. Tomassian  enjoys sports, traveling, world & national affairs and  trains in Tae Kwon Do with a third degree black belt. He served several terms as Past Chairman of the World Affairs Council of Orange County and was honored as Ambassador at Large for the Council. He is also a member of the board of directors and executive board for the World Affairs Councils of America (DC based).

Telephone 949-955-2280 | Email: [email protected]


Professional Recognitions


      AAA Logo 2015                       SuperLawyers_logo


      avvo_superb_rating_           Client Choice  2013-OC-Metro-logo



   AV-Rated-by-Martindale-Hubbell       icon_best_lawyers



To speak with Mr. Tomassian, contact him at the Irvine, California offices of Tomassian, Throckmorton, Inouye & Grigorian LLP at 949-955-2280 or contact him online.

  • Institute of International and Comparative Law, Paris, France, Certificate of Law
  • McGeorge School of Law, University of the Pacific, J.D. (Moot Court Honors Board)
  • University of Southern California, B.A. (Phi Beta Kappa)
  • Orange County Bar Association
  • Chair, Legislative Committee
  • Chair, Construction Law Section
  • Member, OCBA Board of Directors
  • Member, Business, Litigation and International Law section
  • Member, Judiciary Committee section
  • State Bar of California
  • State of California and U.S. District Court, Eastern and Central District of California
Community and Recognitions
  • Chairman, 2001-2003, 2011-2012 and Trustee since 1993 for World Affairs Council of Orange County
  • Orange County Armenian Professional Society
  • Recipient of the Golden Orange Award-2013-World Affairs Council of Orange County
  • OCAPS Award for Service to Community for Armenian Genocide Recognition
  • American Arbitration Association- serve as Mediator and Arbitrator
  • California Legislature Resolutions for Public Service Recognition
  • MVP for Local Bar Association
  • French