An experienced counselor and litigator, Eyitayo “Tee” St. Matthew-Daniel is Deputy Co-Chair of the Antitrust Department. Tee advises clients on a broad range of antitrust issues, including those impacting their interests and operations around the world, leveraging her experience both within the senior ranks of the U.S. Department of Justice’s Antitrust Division and in private practice. Clients describe Tee as “an antitrust expert,” “superb,” and “hugely valuable.”
Tee has been recognized by Chambers USA in the Antitrust: Cartel (Nationwide & Global) and Antitrust (NY) categories, and recommended by Legal 500 in the Antitrust: Civil Litigation/Class Actions: Defense (2024-2025) and Antitrust: Merger Control (2024-2025) categories. In 2024 and 2025, Legal 500 recognized Tee as a “Next Generation Partner” in the Antitrust: Cartel category, and Savoy Magazine named her to their “Most Influential Lawyers” list. In 2023, Law360 named Tee a Rising Star for Competition. In 2022, Tee was awarded the John Hughes Award for Excellence in Cartel Enforcement by the U.S. Department of Justice in recognition of her career achievements and exemplary work ethic.
Dual-qualified in New York and England & Wales, Tee has extensive experience representing global clients in antitrust litigation, complex investigations and regulatory matters. She has secured antitrust clearances from the U.S. Department of Justice, Federal Trade Commission, European Commission and numerous national competition authorities, and has defended clients in civil and criminal investigations across North America, Europe, Africa and the Asia-Pacific.
Recent notable representations as antitrust counsel include:
- Automatic Data Processing (ADP) in its acquisition of WorkForce Software, a premier workforce management solutions provider.
- Charlesbank Capital Partners and its portfolio company Neptune Retail Solutions in Neptune's all-cash take-private acquisition of Quotient Technology, a Utah-based software development company.
- Wynnchurch Capital, LP and its portfolio company Mattress Warehouse as the divestiture buyers in a vertical merger investigation and litigation by the FTC challenging Tempur Sealy International’s proposed $4 billion acquisition of the Mattress Firm Group.
- Redfin in multiple federal antitrust class actions brought on behalf of nationwide classes of home sellers and home buyers alleging that the National Association of REALTORS® and brokerages conspired to inflate commissions paid by consumers.
- Spirit Airlines, in a merger investigation and litigation by the DOJ challenging its $3.8 billion sale to JetBlue Airways, and related private litigation.
- A multinational manufacturing chemical company in an investigation conducted by the DOJ into allegations of collusion in the fragrance industry and related civil litigation.
- A multinational ticketing company in connection with a civil conduct investigation and litigation by the DOJ into allegedly anticompetitive conduct in ticketing and concert promotion services.
Tee previously served in leadership and trial counsel roles in the U.S. Department of Justice’s Antitrust Division. As Assistant Chief in the DOJ's Antitrust Division, she supervised and prosecuted international cartel and labor enforcement cases, updated the Corporate Leniency Policy and directed the Procurement Collusion Strike Force. She also co-chaired the Division’s Diversity Committee and represented the Division on the Attorney General's Diversity Council. Earlier in her DOJ career, Tee served as counsel to the Division's assistant attorney general advising on legal and policy matters, including compliance, international coordination, and investigations in regulated industries such as healthcare and financial services.
Boards and Other Professional Affiliations
Network (ICN). She is a member of the American Bar Association and a committee vice-chair of its Antitrust Law Section, and an Executive Committee member of the New York State Bar Association’s Antitrust Section. She has spoken at many conferences on antitrust and competition trends and developments and served on the faculty of several antitrust programs, including the ABA Antitrust Section’s In-House Institute (2019), International Cartel Workshop (2024) and Antitrust Masters Course (2025).
