LAWYER PROFILE
Bernard O'Sullivan

Bernard O'Sullivan

UK 2026

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Ranked in 1 practice area

About

Provided by CMS

Practice Areas

Bernard advises on all aspects of complex commercial litigation with a particular emphasis on asset recovery, civil fraud and regulatory issues. Bernard frequently acts for both claimants and defendants in high value multi-jurisdictional disputes. Bernard is a member of the advisory board and co-chair of the Informa Asset Recovery conference in Dublin.

Chambers UK 2020 describes Bernard as a "supreme strategist" who is "unflappable, pragmatic and commercial." Chambers UK 2019 noted of Bernard that: "He is a brilliant lawyer who not only knows the law but knows how to achieve positive results efficiently. He understands the various cultural issues that are at play in international fraud cases, and manages various competing interests simultaneously with savvy."

Bernard has in depth experience of securing and defending asset tracing orders including freezing, search, disclosure and Norwich Pharmacal orders. Bernard has also acted as lead litigation adviser for clients in a wide range of jurisdictions (both common law and civil law) including securing appropriate orders and investigations in these jurisdictions.

Prior to CMS he was a partner in Dechert before setting up the niche practice Byrne and Partners.

Chambers Review

Provided by Chambers

Chambers Guide to the Legal Profession

Fraud: Civil - UK-wide

Band 3
Band 3

Individual Editorial

Bernard O'Sullivan leads the fraud practice at CMS and is routinely called upon by clients for his experience in complex litigation and related investigations. He also assists clients with obtaining and resisting applications for injunctive relief across multiple jurisdictions.

Strengths

Provided by Chambers

  • Bernard is a very creative and innovative fraud lawyer.

    Fraud: CivilChambers Guide to the Legal Profession
  • He shows great dedication to his clients and fights hard for them. He is level headed even when events are not progressing well. He is a really good team player.

    Fraud: CivilChambers Guide to the Legal Profession
  • Bernard is fabulous at developing opportunities in the market and is very entrepreneurial in his approach. He brings teams together in an expert way.

    Fraud: CivilChambers Guide to the Legal Profession
  • Bernard brings a level of clarity and strategic focus that is both rare and invaluable, especially in cross-border cases. His ability to assess a situation and provide measured guidance is reassuring.

    Fraud: CivilChambers Guide to the Legal Profession

Ranked Individuals at CMS (216)

London (Firms)

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