Berger Montague

Antitrust Department

Caitlin G. Coslett is a Shareholder and Co-Chair of Berger Montague’s Antitrust Department. Ms. Coslett concentrates her practice on complex litigation, including antitrust, qui tam (whistleblower), and mass tort litigation, and specializes in, among other things, economic experts and class certification issues.

Ms. Coslett also represents classes of direct purchasers of pharmaceutical drugs who allege that drug manufacturers have violated federal antitrust law by wrongfully keeping less-expensive generic drugs off the market and/or by wrongfully impeding generic competition. Her work on antitrust cases challenging conduct that impaired generic pharmaceutical competition has contributed to significant settlements totaling hundreds of millions of dollars, including In re Suboxone (Buprenorphine Hydrochloride and Naloxone) Antitrust Litigation ($385 million settlement), In re Generic Pharmaceuticals Pricing Antitrust Litigation (partial settlements totaling more than $385 million so far), In re Lidoderm Antitrust Litigation ($166 million in settlements), In re Lipitor Antitrust Litigation ($93 million settlement), In re Intuniv Antitrust Litigation ($78 million in settlements), In re Opana ER Antitrust Litigation ($145 million settlement), In re Novartis and Par Antitrust Litigation ($126 million), In re Solodyn (Minocycline Hydrochloride) Antitrust Litigation ($76.8 million in settlements), In re Skelaxin (Metaxalone) Antitrust Litigation ($73 million), In re Effexor XR Antitrust Litigation($39 million settlement).

Ms. Coslett’s experience litigating antitrust class actions also includes In re Cathode Ray Tube (CRT) Antitrust Litigation, In re Domestic Drywall Antitrust Litigation, In re Payment Card Interchange Fee and Merchant Discount Antitrust Litigation, In re Steel Antitrust Litigation, and In re Urethane [Polyether Polyols] Antitrust Litigation.

Ms. Coslett also serves as counsel, including trial counsel, for the plaintiff whistleblower in a False Claims whistleblower case against pharmacy benefits manager Caremark and related entities.  After an eight-day bench trial in March 2025, the Eastern District of Pennsylvania found that the Caremark defendants were liable for false and inflated drug prices that had been reported to the Government for prescriptions filled for Medicare Part D beneficiaries at two national chain pharmacies (Walgreens and Rite Aid), causing the federal government to overpay for these generic drugs. The Court entered a $289,873,500 final judgment on behalf of plaintiff whistleblower. Ms. Coslett and her co-counsel were named Law360 “Legal Lions of the Week” for their work on this case.

Ms. Coslett also played a significant post-trial role in Cook v. Rockwell International Corporation, a mass tort class action brought on behalf of thousands of owners of property near the Rocky Flats nuclear plant in Colorado. The case settled for $375 million following two appeals, including a successful appeal to the Tenth Circuit.  In ruling for the plaintiffs on appeal, then-Judge (now Supreme Court Justice) Neil Gorsuch praised Class Counsel’s successful “judicial jiu-jitsu” in litigating the case through the second appeal.

Ms. Coslett is recognized as a leader in her field.  She is Co-Chair of the Antitrust Committee of the Philadelphia Bar Association and has spoken at numerous events, including at the American Antitrust Institute’s Annual Private Enforcement Conference, and on panels such as “What’s New in Antitrust Doctrine, Procedure, and Research?” (Bar Association of San Francisco, 2022) and “Civil Justice Fest: A Month of Dialogues on the Most Pressing Civil Justice Issues” (Law & Economic Center, George Mason University Law School, 2020). Ms. Coslett won an award for Outstanding Antitrust Litigation Achievement in Private Law Practice from the American Antitrust Institute in 2024 for her work in In re Suboxone Antitrust Litigation and was honored for “Outstanding Antitrust Litigation Achievement by a Young Lawyer” by the American Antitrust Institute in for her work in In re Lidoderm Antitrust Litigation. Ms. Coslett was also named a “Leading Partner” by The Legal 500 United States in the Civil Litigation/Class Actions: Plaintiff category and was selected as a Rising Star by Super Lawyers every year from 2014-2026. She has served as pro bono co-counsel with the AIDS Law Project of Pennsylvania and the Women’s Law Project, and as counsel for clients referred by Philly VIP, is a member of the Board of Directors for Community Legal Services, and is a member of the National LGBT Bar Association.

Ms. Coslett graduated magna cum laude from Haverford College with a B.S. in mathematics and economics and graduated cum laude from New York University School of Law. At NYU Law, Ms. Coslett was a Lederman/Milbank Fellow in Law and Economics and an articles selection editor for the NYU Review of Law and Social Change.

Prior to law school, she was an economics research assistant at the Federal Reserve Board in Washington, D.C. Ms. Coslett was formerly a nationally ranked chess player and a member of several national championship scholastic teams, and she currently runs chess tournaments for a Philadelphia non-profit organization.