O’Melveny Worldwide

Lauren M. Weinstein

Partner

Washington, DC Office
Areas of Focus
Areas of Focus
Antitrust & Competition
Antitrust Counseling & Compliance
Supreme Court & Appellate Litigation
Overview Experience Insights News Credentials

Lauren Weinstein is a partner in O’Melveny’s Washington, DC office. Her practice focuses on trial and appellate litigation, with a focus on antitrust and complex commercial disputes, particularly in the media and technology, financial services, and real estate industries. She represents clients before the United States Supreme Court, the federal courts of appeals, and state and federal trial courts nationwide. Her practice covers a broad array of subject matters, including antitrust law, class actions, constitutional law, business litigation, and securities suits. Lauren served as Co-Chair of the ABA Section of Litigation’s Antitrust Litigation Committee for three years and currently serves as a Division Director within the ABA Litigation Section, where she is responsible for the Antitrust Litigation Committee.

Lauren has extensive experience in high-stakes antitrust litigation. She was appointed as a Special State Attorney General to prosecute antitrust and consumer protection claims on behalf of 39 states in the In re Google Play Store Antitrust Litigation. She also represented the nation’s largest publicly traded holding company for real estate brokerage brands in a price-fixing class action, securing a favorable pretrial settlement that avoided the nearly US$5 billion verdict the jury rendered against the remaining co-defendants.

Prior to her private practice experience, Lauren clerked for the Honorable M. Margaret McKeown of the United States Court of Appeals for the Ninth Circuit and the Honorable John G. Koeltl of the United States District Court for the Southern District of New York. Lauren has been recognized as an “Up and Coming” practitioner in Antitrust by Chambers USA, a Rising Star by Super Lawyers and Legal 500, and a Leading US Litigator and Next Generation Leader by Lawdragon.

Get to Know Lauren

Get to Know Lauren

  • Representing TikTok/ByteDance in the defense of actions brought by the Attorneys General of 29 states and the District of Columbia alleging unfair trade practices, product liability, and public nuisance claims. These matters, litigated in courts from Hawaii to New Hampshire, present some of the most complex factual, statutory, and constitutional issues in mass torts litigation today.
  • Advising a diagnostic company on a strategy for proactive state attorney general engagement related to alleged anti-competitive practices by a competitor concerning patient/provider choice and competition.
  • Providing ongoing antitrust and compliance counseling to Home Depot.
  • Advising an online travel marketplace on a multipronged strategy for proactive state attorney general engagement in an effort to mitigate short-term rental restrictions set by municipalities and preempt municipal ordinances.
  • Representing a global tech giant in a dispute with OpenAI regarding the performance of a technology agreement.
  • Represented 39 State Attorneys General prosecuting a leading technology company for alleged monopolization of app-store and related markets, resulting in historic US$700 million settlement.
  • Defended nation’s largest publicly traded holding company for real estate brokerage brands in a price-fixing class action, securing a favorable pretrial settlement that avoided the nearly US$5 billion verdict the jury rendered against the remaining co-defendants.
  • Advising global investment manager on potential antitrust claims against a business partner.
  • Represented leading antitrust scholars as amici curiae in the Supreme Court in the leading case on who qualifies as a direct purchaser under the federal antitrust laws.

Admissions

Bar Admissions

  • District of Columbia

Education

  • Harvard Law School, J.D.
  • Northwestern University, B.A., Political Science and Legal Studies: magna cum laude

Honors & Awards

  • Recognized by Chambers USA in Antitrust: Litigation Specialists (2024-2026)
  • Best Lawyers: Ones to Watch in America – Litigation – Antitrust (2024, 2027)
  • Ranked Band 1 and Washington DC elite for Antitrust by Legal 500 US (2022-2026)
  • The Next Generation, Complex Commercial Litigation, esp. Antitrust, Lawdragon 500 X (2023-2025)
  • American Bar Foundation, Fellow (elected 2024)
  • Washington, D.C. Super Lawyers, SuperLawyer (2024-2026) & Rising Star (2021-2023)
  • Leading Litigators in America, Complex Commercial Litigation, esp. Antitrust, Lawdragon 500 (2022, 2023)
  • Leadership Council on Legal Diversity Fellow (2020-2021)
  • Hispanic National Bar Association Top Lawyers Under 40 Award (2019)
  • Honorable Judith Kaye, Commercial and Federal Litigation Scholar, New York Bar Foundation (2017)
  • J. William Fulbright Grant Recipient, France (2007-2008)

Professional Activities

Member

  • ABA, Antitrust Law Section: Media and Technology Committee; Counseling and Compliance Committee
  • ABA, Litigation Section: Division Director (2024-2025); Co-Chair, Antitrust Litigation Committee (2020-2023); Co-Chair, Section Annual Conference (2023-2024)
  • ABA Commission on Hispanic Legal Rights & Responsibilities (2020-present)
  • Hispanic National Bar Association
  • Law360 Editorial Advisory Board – Competition
  • New York State Bar Association, Antitrust Section
  • Roderick & Solange MacArthur Justice Center Appellate Advisory Board

Publications

  • “Assessing Potential Ad Tech Remedies Ahead Of Google Trial,” Law360 (September 18, 2025)
  • “Recent Developments in State Laws and Potential Risks for Healthcare Investors,” Corporate Counsel (September 15, 2025)
  • “Antitrust Magazine Roundtable Discussion on State Enforcement,” Antitrust, Vol. 39 No. 2 (Spring 2025)
  • “Google And The Next Frontier Of Divestiture Antitrust Remedy,” Law360 (September 23, 2024)
  • “Rising Risks for PE Firms to Monitor Amidst Changing Antitrust, Whistleblower and Sanctions Landscape,” Private Equity Law Report (January 11, 2024)
  • “AmEx Ruling Proves A Double-Edged Sword In Labor Antitrust,” Law360 (April 13, 2023)
  • “4th Circ. Opens Door to New Private Merger Enforcement Era,” Law360 (March 9, 2021)
  • “New York's Latest Experiment in Antitrust Law,” New York Law Journal (March 1, 2021)
  • “How Credit Card Fee Antitrust Cases Fare In UK Versus US,” Law360 (September 9, 2020)
  • “4th Circ. Seems Leery of Divestiture Order in Doormaker Case,” Law360 (June 1, 2020)
  • “Antitrust Rules Still Apply During COVID-19,” Law360 (March 27, 2020)
  • “Courts Face Controversy Over Uninjured Antitrust Class Members,” National Law Journal (February 27, 2020)
  • “Door Maker Merger Case May Transform Behavioral Remedies,” Law360 (August 2, 2019)
  • “App Store Opinion Returns Antitrust Enforcement To Its Roots,” Law360 (May 29, 2019)
  • “Lessons I've Learned As a Young Woman Lawyer,” New York Law Journal (September 14, 2017)

Speaking Engagements

  • “The Role of State Attorney Generals in Antitrust Enforcement,” NYU Annual Survey of American Law Spring Symposium (2026)
  • “Antitrust in the New Administration, American Bar Association,” Litigation Section Annual Conference (2025)
  • “Labor Markets & Antitrust in Brazil and the United States,” Cascione Advogados Webinar (2024)
  • “Antitrust Update, Remedy & Ramifications,” adMarketplace's IMPACT Conference (2024)
  • “Big Tech on Trial,” ABA Litigation Section Annual Conference (2024)
  • “Developments in Criminal Antitrust Prosecutions,” Seventh Circuit Bar Association Webinar (2024)
  • “Tips for Handling Non-Competes and Employment Issues in Today's Antitrust Climate,” ABA Litigation Section Roundtable (2024)
  • “Putting Antitrust Law to Work,” ABA Litigation Section Corporate Counsel Conference (2023)
  • “How to Break into Antitrust Law as a Young Lawyer,” ABA Young Lawyers Division Webinar (2022)
  • “Non-Competes Under Attack,” ABA Litigation Section Corporate Counsel Conference (2022)
  • “Trust-Busting the Tech Titans,” ABA Litigation Section Annual Meeting (2021)
  • “Is 'Abuse of Dominance' Coming to the US,” ABA Antitrust Section Roundtable (2021)
  • “New York Women in Antitrust: Lessons Learned in Life and Law” (2021)
  • “Apples & Economics: Is Illinois Brick Obsolete?,” ABA Antitrust Law 2020 Spring Meeting (2020)
  • “Antitrust Basics,” Harvard Law School (2019)
Related Practices
Antitrust & Competition
Antitrust Counseling & Compliance
Corporate Social Responsibility & Sustainability
Litigation & Investigations
Regulatory & Advisory
Supreme Court & Appellate Litigation