Y. Michael Twersky

Biography

Yechiel Michael Twersky concentrates his practice on representing plaintiffs in complex litigation, with a primary focus on environmental and insurance matters. He also has experience across a broad range of other areas, including Lanham Act litigation and antitrust actions.

Mr. Twersky currently devotes much of his practice to representing the Commonwealth of Pennsylvania, the State of Maryland, and the State of New Jersey as Special Counsel in MTBE litigation, in which the state plaintiffs have brought claims against major oil companies for groundwater contamination. He has also been retained by a state as part of a team tasked with investigating claims involving alleged PCE contamination. In these governmental matters, he plays a significant role and has developed deep familiarity with the unique challenges of serving as Special Counsel, the defenses commonly asserted against state plaintiffs, and the complexities of prosecuting claims against multinational defendants prepared to litigate for decades.

In addition to his governmental work, Mr. Twersky represents private plaintiffs in environmental and contamination matters. His work includes representing individuals and property owners in litigation against multiple defendants—including Sunoco Pipeline, L.P.—arising from a pipeline leak in Upper Makefield, Pennsylvania.

He also represents private plaintiffs in a case involving several entities in the U.S. Virgin Islands, asserting claims related to contamination associated with the 2021 restart of the Limetree Bay Refinery.

Earlier in his career, Mr. Twersky gained substantial experience in complex antitrust class actions involving allegations that pharmaceutical manufacturers unlawfully delayed the entry of lower‑cost generic drugs. His work included significant involvement in In re Skelaxin (Metaxalone) Antitrust Litigation, 1:12‑md‑02343 (E.D. Tenn.) ($73 million settlement), and In re Solodyn Antitrust Litigation, 14‑md‑2503 (D. Mass.) (combined settlements exceeding $76 million in 2018).

Additionally, Mr. Twersky has litigated numerous complex insurance class matters, including a case in which a federal district court granted summary judgment in favor of the plaintiffs, finding that a major insurance company breached its policy when it denied benefits under an accidental-death insurance plan. Most recently, he played a key role in securing class certification in a loss‑of‑use insurance case against Liberty Mutual. See Watts v. Liberty Mut. Pers. Ins. Co., 2025 WL 3458298 (D. Mass. Dec. 2, 2025).

Mr. Twersky earned his J.D. from Temple University Beasley School of Law, where he was a member of the Rubin Public Interest Law Honors Society and served as a Class Senator. He also advised small businesses and nonprofit clients through Temple’s Business Law Clinic.member of the Rubin Public Interest Law Honors Society and a Class Senator. In addition, Mr. Twersky advised various clients in business matters as part of Temple University’s Business Law Clinic.