Yoosun Koh is a Counsel in the Antitrust Department, with a practice focused on high-stakes government investigations, cartel enforcement matters, and complex litigation. She advises global clients on criminal and civil antitrust matters, with particular experience handling investigations by the U.S. Department of Justice’s Antitrust Division and the Federal Trade Commission. She also frequently serves as coordinating counsel on cross-border cartel matters, helping clients navigate multi-jurisdictional strategy and engagement with leading competition authorities worldwide.
In addition to her antitrust work, Yoosun represents companies and individuals in sensitive white collar investigations and enforcement actions. Her experience includes matters involving the DOJ, the Securities and Exchange Commission (SEC), the Financial Industry Regulatory Authority (FINRA), and state attorneys general, with a substantive focus on securities fraud, investment advisory fraud, healthcare fraud, the False Claims Act, and the Foreign Corrupt Practices Act.
Yoosun also maintains an active complex litigation practice, representing clients in high-stakes commercial disputes. She was a member of the trial team representing Oracle in Oracle USA, Inc. v. Rimini Street, Inc., securing a trial victory and permanent injunction in a significant copyright case.
Yoosun’s notable representations include:
- American Iron & Metal (“AIM”), a global leader in the metal recycling industry, in a series of NYS administrative law challenges brought by a competitor related to the redevelopment of a property as a metals recycling facility following a multi-million dollar environmental remediation under the Brownfield Cleanup Program.
- Invitation Homes (IH), a national single-family home leasing company, in a favorable settlement with the FTC resolving the FTC’s three-year investigation into and claims against IH regarding its home rental practices generally and during the COVID-19 pandemic specifically.
- Oracle as trial counsel in its long-running dispute with software services provider Rimini Street over whether Rimini’s third-party software support violates Oracle’s copyrights.
- A multinational manufacturing chemical company in an investigation conducted by the DOJ into allegations of collusion in the fragrance industry and related civil litigation.
Prior to joining the firm, Yoosun served as an Assistant United States Attorney for the Northern District of California, where she investigated and prosecuted a broad range of complex crimes. She has federal trial experience, including delivering opening statements, examining expert witnesses, and presenting closing arguments.
Earlier in her career, Yoosun completed a secondment as in-house counsel in the global financial crimes group of a major financial institution.
Yoosun holds a J.D. from the University of California, Berkeley School of Law, an M.Phil. in International Relations from the University of Cambridge, and a B.A. (Philosophy, Politics, and Economics) from the University of Oxford.
