Irish Legal 100


THOMAS F. O’Neil III is a highly respected adviser and corporate director with broad private and public sector experience, including leadership roles in the boardrooms and C-suites of companies in the consumer, financial services and healthcare sectors.

A governance, compliance and risk management thought leader, he collaborates with financial sponsors, corporate boards and leadership teams to drive ethical and sustainable growth through disruptive innovation and fulfillment of stakeholder expectations.

During a distinguished career spanning several decades, O’Neil has developed an exceptional track record of accelerating cultural transformation and restoring trust with regulators, enforcement officials and investors. He has chaired the audit and risk oversight, ethics and compliance, and nominating and governance committees of corporate and mutual fund boards.

In his most recent corporate role, O’Neil was the global chief compliance officer of Cigna Corporation, a leading health service company with over 70,000 employees and approximately $160 billion in top-line revenue. He has held a number of other positions in public companies, including executive vice chairman, general counsel and secretary of WellCare Health Plans, Inc. and senior vice president and general counsel of the MCI Group.

O’Neil has also been a partner at two global law firms, DLA Piper LLP (US) and Hogan & Hartson (now Hogan Lovells US LLP). During his tenure at DLA Piper, he was a joint global practice group leader and he chaired the U.S. Government Affairs Practice Group.

O’Neil joined Berkeley Research Group (BRG) in 2021; The Saranac Group LLC, the strategic consulting firm that he founded in 2010, is now a BRG affiliate.

Earlier in his career, O’Neil served as an assistant U.S. attorney in the District of Maryland, a law clerk to U.S. District Judge Alexander Harvey II, and a legislative assistant to former Congressman Stewart B. McKinney.

He received an AB, magna cum laude, from Dartmouth College and a JD from Georgetown University Law Center.

O’Neil is a former member of Georgetown’s Board of Regents, the Board of Visitors of the Law Center and the Board of Trustees of the Walters Art Museum. He also served as co-chair of the Advisory Board of the Georgetown Corporate Counsel Institute.

O’Neil’s paternal grandfather came from Co. Tyrone. He and his wife, Nancy, whose family is from Co. Sligo, live in Baltimore.





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