Former Antitrust Division Criminal Chief Ryan Tansey is a seasoned antitrust attorney, litigator, and first-chair trial lawyer. Whether representing clients in high-stakes criminal investigations, civil class actions, or jury trials, Ryan leverages his substantial experience and a decade at the U.S. Department of Justice shaping national antitrust enforcement and leading some of the Department’s most complex matters across multiple components and four presidential administrations.
Ryan guides clients through every phase of criminal and civil antitrust matters, as well as broader commercial disputes and white-collar cases. He represents clients in federal and state investigations, litigates civil class actions, and counsels on antitrust compliance and proactive risk management. As a true first-chair trial lawyer, Ryan is one of very few antitrust practitioners who also has the skill and experience to lead the most complex cases from inception through to trial and successful jury verdict. He is known for his strategic vision and helping clients formulate a strategy that balances legal risks, collateral consequences, and reputational concerns.
Before joining King & Spalding in June 2026, Ryan served as Chief of the Antitrust Division's largest section in Washington, D.C., where he supervised hundreds of grand jury investigations, charges, plea agreements, and trials nationwide. He oversaw a landmark DPA with Teva Pharmaceuticals, securing a $225 million criminal fine—the largest ever in a domestic antitrust cartel case—with unprecedented criminal divestitures. His team of 90 prosecutors and staff handled matters across industries including technology and AI, telecommunications, healthcare, financial services, energy, and defense contracting. Ryan also helped shape national antitrust enforcement policies, including launching the Division's inaugural Whistleblower Rewards Program, and worked closely with foreign competition authorities, state attorneys general, and federal agencies on parallel investigations and litigations.
Earlier in his career, Ryan was a go-to litigator in multiple DOJ components. As a Trial Attorney in the Antitrust Division, he led one of the decade's most significant international cartel prosecutions, resulting in five corporate convictions and over $363 million in penalties. As an Assistant U.S. Attorney, he led an office and prosecuted complex cases ranging from securities fraud and bribery to murder-for-hires and large pill mill prosecutions. He has also led many complex trials to favorable verdicts and received numerous DOJ accolades for his trial work, including the EOUSA Director's Award and selection as a returning instructor at DOJ's criminal trial advocacy course.
Prior to DOJ, Ryan practiced at another leading international law firm, defending clients in civil and criminal antitrust matters, including MDLs, class actions, and investigations concerning LIBOR, Forex, interchange fees, and global shipping.
Beyond his client work, Ryan is an active voice in the antitrust bar, regularly engaging with practitioners, corporate leaders, and policymakers through speaking engagements, panel discussions, and industry forums on the issues shaping competition enforcement. Some recent examples include:
- Panelist, NYSBA Antitrust Law Section Webinar (2026), discussing grand jury investigations, leniency strategy, witness preparation, and parallel antitrust proceedings.
- Panelist, GCR Live: Cartels 2026 (2026), discussing cartel enforcement trends, whistleblower programs, compliance, and investigative developments.
- Speaker, GCR Live: Cartels 2025 (2025), discussing information sharing and antitrust risks arising from developing technologies.
- Panelist, OECD Competition Open Day (2024), addressing emerging issues in global antitrust and competition law.
- Speaker, American Bar Association Antitrust Spring Meeting (2024), discussing AI, algorithmic information sharing, and criminal antitrust enforcement risks.
- Panelist, Information Exchanges: What Is Safe? (ABA Antitrust Law Section, 2024), examining information-sharing practices, AI-related risks, and recent antitrust enforcement developments.
