Sonia Kuester Pfaffenroth

Sonia Kuester Pfaffenroth is a partner in the Antitrust/Competition practice at Arnold & Porter in Washington, DC. She represents companies in civil antitrust litigation, reviews of mergers and acquisitions and criminal investigations as well as advising on antitrust compliance and providing day-to-day counseling on a wide variety of competition issues. She previously served in the Antitrust Division of the US Department of Justice in a variety of positions, most recently as Deputy Assistant Attorney General for Civil and Criminal Operations, where she was responsible for supervising civil and criminal antitrust enforcement efforts, as well as the Division’s work with antitrust and competition law enforcement agencies worldwide.