Hahn & Hahn LLP


D. Jason Lyon

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D. Jason Lyon

Pasadena, California
626.796.9123 x342
D. Jason Lyon is a litigation partner at Hahn & Hahn LLP. His practice focuses on commercial litigation involving complex financial matters and intricate fact patterns. Prior to joining Hahn & Hahn, Mr. Lyon was an associate with Latham & Watkins, practicing in the Complex Commercial Litigation and Securities Litigation groups. Mr. Lyon earned his BA in film and television from the University of North Carolina at Chapel Hill and his J.D. from the UCLA School of Law (Law Review, Michael T. Masin Scholar, Order of the Coif). He is a member of the Pasadena Bar Association, the Los Angeles County Bar Association, the State Bar of California, and the American Bar Association, in addition to the LGBT Bar Association. He is admitted to practice in all courts in the state, the Ninth Circuit Court of Appeals, and the Northern and Central federal district courts. Los Angeles Business Journal has twice named Mr. Lyon one of Los Angeles County's top diverse attorneys and a Leader of Influence in Litigation. In 2021, the LA Times B2B Publishing named Mr. Lyon a Visionary in the Business of Law.
Bar Admissions 

University of North Carolina at Chapel Hill, B.A.
UCLA School of Law, J.D. (UCLA Law Review, Michael T. Masin Scholar, Order of the Coif)

Honors and Awards 

Diversity, Inclusion, Equity and Accessibility Visionary, L.A. Times B2B Publishing, 2023
Federal Bar Association Judge Barry Russell Award
Leaders of Influence: Minority Attorneys, Los Angeles Business Journal, 2020

Charitable and Community Leadership and Professional Associations 

American Bar Association
Los Angeles County Bar Association
Pasadena Bar Association
LGBT Bar Association
City of Pasadena - Board of Zoning Appeals 2020
City of Pasadena - Planning Commission 2019
Planned Parenthood Pasadena and San Gabriel Valley - Board of Directors 2019
City of Pasadena - Historic Preservation Commission 2018-2019
San Gabriel Valley Economic Partnership - Board of Directors 2018 - 2019
Western Justice Center - General Counsel - 2018-2019
All Saints Pasadena - Senior Warden 2016-17, Junior Warden 2015-16, Vestry 2013-17
Young & Healthy - President 2017 - 2019, Vice President 2016 - 2017, Board of Directors 2014 - 2019
LA County Bar Association Access to Justice Committee, 2016-2017
City of Los Angeles - Neighborhood Council Review Commission, Vice Chair 2006 – 2008
City of Los Angeles - East Los Angeles Area Planning Commission Commissioner 2004 – 2005
City of Los Angeles - Silver Lake Neighborhood Council, Co-Chair 2003-05, Governing Board 2003-07
Silver Lake Reservoirs Conservancy, Board Member 2007 – 2008

Representative Cases 

Lead litigator representing major medical billing service provider in multi-million dollar breach of contract, conversion, and fraud claim against collection agency, resulting in Confession of Judgment and full restitution
Won a five-day trial as lead counsel defending a substantial family estate against a challenge to the legitimacy of its governing trust instrument and alleged malfeasance
Represented plaintiff professor in discrimination claim against private university resulting in substantial settlement
Devised successful pre-litigation risk mitigation strategy for high net-worth client in dispute with start-up business partner

Current matters include:
Represent medical partners in fraud and related claims against healthcare entity that acquired their practice
Shareholder derivative claims involving closely held family wholesale business
Defense of fraud and conversion claims in failed real estate venture
Defense of theft of trade secrets and related claims