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Brandon O'Neil



ONeil Brandon
Brandon O'Neil



Brandon focuses on complex cross-border regulatory investigations, financial crime matters and litigation, with particular experience representing financial institutions. He advises clients on a broad range of issues such as insider trading, anti-money laundering, asset tracing and judgment enforcement, fraud and bribery.

Brandon represents both institutions and individuals in cross-border investigations involving a range of regulators in the U.S. (DOJ, SEC, CFTC), Europe (UK FCA, SFO) and Asia. He has particular expertise in investigations involving insider trading, money laundering, market manipulation, bribery and fraud. In addition to England and Wales, Brandon is admitted to the Bar of the State of New York and worked for a number of years in A&O’s New York office. Given the critical importance of U.S. law in contentious regulatory investigations and the far-reaching impact of U.S. authority-led investigations, this dual-experience brings valuable insight and experience to clients when they experience multi-jurisdictional, multi-agency investigations. Brandon also has substantial experience in submitting and defending private criminal complaints in continental European jurisdictions.

Brandon’s litigation practice focuses on cross-border fraud, asset tracing and judgment enforcement matters. Brandon’s dual New York and English qualification, together with his extensive experience litigating in various jurisdictions around the world, brings the cross-border outlook needed to successfully pursue (or defend) complex cases of this type. In addition to experience in such cases in the UK courts, Brandon has represented clients in numerous such enforcement cases across Europe, the U.S., the Caribbean and Asia, seeking to recover a broad range of assets ranging from art to real estate.

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Blog Post: 25 November 2021

Sustainability disclosures and enforcement risk: Reflections on COP

At COP26, Nikhil Rathi, CEO of the UK's Financial Conduct Authority (the FCA), warned the financial services industry that it was time to "walk the walk". In the wake of the recent wave of…

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Publications: 10 September 2021

Lessons learned on taking security in a commodity finance transaction

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Blog Post: 08 July 2021

UK corporate criminal liability reform

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Publications: 02 September 2020

Direct access: a sea change in data gathering in U.S./UK criminal investigations

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Admitted: Bar of the State of New York, 2009

Admitted: U.S. District Court, Southern District of New York, 2009  


J.D., Columbia Law School, 2008

M.A., University of Wyoming, 2004 

B.A., University of Wyoming, Phi Beta Kappa, 1999