
Sheppard, Mullin, Richter & Hampton is pleased to announce that Ann M. O’Brien has joined the firm as a partner and co-leader of the Antitrust & Competition practice group. She will also lead the firm’s Criminal Antitrust and Cartels team.
Based in Washington, DC O’Brien was most recently the leader of the Cartel and Government Antitrust Investigations Task Force at BakerHostetler.
O’Brien advises clients facing criminal and civil government antitrust investigations or litigation. She has extensive knowledge of antitrust enforcement practices and policy decisions, gained from her time working for nearly 20 years at the US Department of Justice (DOJ) in the Antitrust Division and as a Special Assistant United States Attorney in the District of Maryland.
Over her tenure, she served in numerous senior leadership and management positions at the Antitrust Division, notably as the Assistant Chief of two sections and as the Acting Director of Criminal Enforcement.
Read more: Sheppard Mullin Expands DC Office With Antitrust Partner
As acting director, O’Brien was the second-highest career official and highest ranking woman running the Antitrust Division’s criminal program, where she supervised more than 120 attorneys across five offices. During her two-decade DOJ tenure, O’Brien was involved in virtually every major criminal enforcement and policy decision made by the Antitrust Division.
“Ann is a well-known, trusted advisor whose DOJ training and compliance counseling will help our clients deter or quickly detect antitrust exposure, informed by what is most important to the Antitrust Division and the courts,” said Luca Salvi, chair of Sheppard Mullin.
“In addition to her client work, Ann’s proven ability to lead large teams both at the DOJ and in private practice to successful outcomes and mentor antitrust attorneys early in their careers to blaze a path forward makes her an ideal fit for our culture and our firm.”
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