Antitrust
USA Guide 2026 : District of Columbia
Rankings

Ranked Individuals
Ranked Individuals
About
Provided by O'Melveny & Myers LLP
Consistently ranked among the top global antitrust practices, we bring credibility and teamwork to everything we do, from precedent-setting courtroom victories to deft handling of merger reviews by agencies around the world.
Our litigation abilities range from extricating clients early and efficiently to achieving . And when it comes to shepherding transactions through global clearance processes, we are practice leaders. We routinely handle complex international mergers and obtain clearance in challenging situations.
We have a reputation for sophisticated, practical antitrust strategy that couples cutting-edge economic and doctrinal analyses with an adept reading of the regulatory and political environment, even under the tightest timeframes. And we are one of the few firms whose partners have tried—and won—cases for and against, the government.
With a team that includes veterans of the US Department of Justice’s Antitrust Division and the Federal Trade Commission, we offer clients an insider’s perspective, bolstered by our close partnerships with renowned economists and consultants.
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Work Highlights
Provided by Chambers
O'Melveny & Myers LLP advised AT&T in responding to a Civil Investigation Demand in connection with the DOJ's investigation of T Mobile’s proposed acquisition of UScellular.
Strengths
Provided by Chambers
O'Melveny & Myers have a strong understanding of the challenges and good insight on the market. They are always available, prepared and provided strategy throughout.
Antitrust respondentUSAO'Melveny are subject matter experts on a wide array of issues and is a go-to law firm for all complex and sophisticated matters. They relay complex concepts in an easily digestible manner and produce excellent work product.
Antitrust respondentUSAO'Melveny & Myers are very practical and knowledgeable. They give business-oriented and straightforward advice. They have significant experience and expertise and regularly interact with the agencies to assist clients.
Antitrust respondentUSA
Notable Practitioners
Provided by Chambers
Band 3 
Band 3 
Ian Simmons
Ian Simmons co-chairs the antitrust practice at the firm. He is a trial lawyer noted for his decades of experience litigating in the space. He has notable expertise in price-fixing cases and also handles governmental investigations.
Ian is phenomenal with the subject matter and he leads the way in understanding tricky and very difficult areas.
Antitrust respondentUSAIan is a very strong advocate and master of antitrust law. He deploys his experience well in his strategy.
Antitrust respondentUSA
Band 5 
Band 5 
Lauren Weinstein
Lauren Weinstein is a talented practitioner who advises clients on sophisticated antitrust litigation. She often represents clients in the technology space.
Lauren is incredibly smart. She understands the issues and provides invaluable insight and practical advice.
Antitrust respondentUSA
Up and Coming 
Up and Coming 
Brian Quinn
Brian Quinn is commended for his experience across a broad range of antitrust matters. He is particularly strong at handling price-fixing disputes and counseling clients.
Brian is an extremely bright and strategic thinker. He is great to work with and handles complex matters with professionalism and sophistication.
Antitrust respondentUSABrian is very bright and experienced.
Antitrust respondentUSABrian was dedicated and very knowledgeable in the space. He was very instrumental in our success.
Antitrust respondentUSABrian is very accomplished. He oozes quality, is all over the detail in a complex case and his drafting is top quality.
Antitrust respondentUSA
Ranked Individuals at O'Melveny & Myers LLP (3)
Members
Provided by O'Melveny & Myers LLP

Ian Simmons
View profile of Ian Simmons
Brian Quinn
View profile of Brian Quinn
Lauren Weinstein
View profile of Lauren Weinstein
O'Melveny & Myers LLP has rankings in the following guides
Band 4
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