Chambers Review
Provided by Chambers
Antitrust - California
What the Team is Known For
Notable practitioners
Leo Caseria is a key contact.

Provided by Sheppard, Mullin, Richter & Hampton LLP
Sheppard delivers practical advocacy in complex antitrust and competition matters worldwide, from cartel investigations to antitrust litigation to merger reviews. With former DOJ, FTC and DG Comp officials, global reach and proven trial success, we deliver strategic antitrust solutions for complex matters.
Recognized as a top practice for antitrust with standout strengths in cartel matters, civil litigation and class action defense and merger control, we are known for offering clear and pragmatic advice.
We help companies and executives contain business risk by anticipating government tactics, moving quickly to identify early resolution opportunities and advancing business priorities. When litigation is necessary, our team’s record of court victories sets us apart.
Our lawyers guide mergers and acquisitions through DOJ and FTC reviews, manage Hart-Scott-Rodino (HSR) filings and coordinate multi-jurisdictional matters for leading clients in technology, healthcare, life sciences, energy, financial services, aerospace and defense, media and consumer products. We play central roles in groundbreaking cases involving big tech, digital platforms, AI, data-driven pricing and healthcare antitrust challenges.
Provided by Chambers
Leo Caseria is a key contact.
Provided by Sheppard, Mullin, Richter & Hampton LLP
Ann O'Brien
Head of Department
Jared Nagley
Leo Caseria
Head of Department
Provided by Sheppard, Mullin, Richter & Hampton LLP
Blue Shield of California
CalPortland Company
Cyient
Duke University
Hartford HealthCare
Prospect Medical Holdings
VillageMD
Provided by Sheppard, Mullin, Richter & Hampton LLP
Aerospace
Automobiles and Parts
Construction Materials
Energy
Food and Drink Producers
Healthcare
Multifamily
Technology