An accomplished trial lawyer, negotiator, and advisor to three presidential administrations, Amb. Robert C. O’Brien joins Signature Resolution after decades of getting results in the most important legal and policy matters of our lifetimes. As a Signature neutral, he will assist parties in resolving cases involving business and commercial contracts, real estate contracts, class actions, employment, entertainment, complex litigation, general liability and malpractice and securities.
O’Brien is well-known nationally for his work as a trial lawyer, having served as lead trial and appellate counsel in high-profile commercial litigation matters and international arbitration cases. He is the co-founder of Larson O’Brien LLP and currently is Of Counsel at Larson LLP. O’Brien was named one of the Top 100 Lawyers in California by the Daily Journal.
He has also served as a special master for numerous federal and state court cases, including MGA v. Mattel (“Barbie v. Bratz”), United States v. Standard & Poors, and In re Allergan Securities Litigation. Additionally, O’Brien has served as an arbitrator in more than two dozen domestic and international matters.
In addition to his legal work, O’Brien has had a robust career in government. O’Brien served as the United States 28th National Security Advisor from 2019-2021. During his time in office, the United States orchestrated the historic Abraham Accords, which brought peace to the Middle East, brokered economic normalization between Serbia and Kosovo, and negotiated significant defense spending increases among our NATO partners.
O’Brien previously served as a U.S. Representative to the UN General Assembly, Co-Chairman of the Department of State Public-Private Partnership for Justice Reform in Afghanistan, and Special Presidential Envoy for Hostage Affairs with the personal rank of Ambassador.
- Larson O’Brien, Founding Partner (2016-2019); Of Counsel, Larson LLP (2021-present)
- Arent Fox LLP, West Coast Managing Partner (2007-2015)
- United States National Security Advisor (2019-2021)
- U.S. Department of State, Special Envoy for Hostage Affairs (2018-2021)
- United States Cultural Property Advisory Committee, Member (2008-2011)
- United States Department of State Public-Private Partnership for Justice Reform in Afghanistan, Co-Chairman (2007-2011)
- United States Alternate Representative to the 60th Session of the United Nations General Assembly (2005-2006)
- United Nations Security Council, Government Claims Section, (Compensation Commission), Team Leader ( 1996-1998)
- J.D., Boalt Hall School of Law, U.C. Berkeley
B.A., cum laude, Political Science, U.C.L.A.
AWARDS, HONORS, MEMBERSHIPS
AWARDS, HONORS, MEMBERSHIPS
- Dr. Miriam and Sheldon Adelson Award for Defense of America and Israel, The Zionist Organization of America (2019)
- Stefan A. Riesenfeld Memorial Award for contributions to the field of international law, Boalt Hall School of Law, U.C. Berkeley (2011)
- Marc Fleischaker Pro Bono Award for contributions to the public good, Arent Fox LLP (2011)
- Erwin Chemerinsky Defender of the Constitution Award, Federal Bar Association (Riverside Chapter) (2009)
- Outstanding Lawyer Award, J. Reuben Clark Law Society (Los Angeles Chapter) (2009)
- Cardinal Newman High School Alumni Scholarship/Leadership Award for Public Service (2006)