Catherine Simonsen is a partner and co-founder of Simonsen Sussman LLP, a boutique, plaintiff-side antitrust litigation firm. Catherine has over a decade of experience investigating and litigating government and private antitrust cases on both the plaintiff and defense sides in federal and California state courts. Prior to co-founding the firm, Catherine served as the Assistant Regional Director for the Western Competition Group at the Federal Trade Commission, where she managed several merger and conduct investigations, and as Senior Legal Fellow for the American Economic Liberties Project. Before joining the FTC, Catherine served as a Deputy Attorney General in the Antitrust Section of the California Attorney General’s office and was a partner at an Am Law 100 international law firm. Catherine holds a J.D. from Yale Law School and a B.A. from Stanford University.
