William G. Cosmas


Mr. Cosmas’ practice focuses on complex litigation and arbitration, both domestic and international, involving life sciences, technology, and finance. His practice also includes probate and fiduciary disputes, and real estate matters. He also represents clients in connection with government investigations and white-collar criminal litigation. In a 2014 pro bono matter, Mr. Cosmas successfully represented an individual in obtaining a pardon from the Commonwealth of Massachusetts, one of the first such pardons granted since 2002.



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Education And Distinctions

  • Boston College Law School, J.D.; Member, National Environmental Moot Court Team
  • Georgetown University, A.B. Philosophy
  • Named Massachusetts Rising Star 2009-2018

More about William G. Cosmas

  • Mr. Cosmas joined FITCH as an Associate upon his graduation from law school, after working as a law clerk there during law school. Prior to attending law school, Mr. Cosmas worked at public relations firms in New York City, where he focused on pharmaceutical and corporate communications.
  • During his third year in law school, Mr. Cosmas participated in Boston College Law School’s Environmental Law Teaching Program, through which he co-taught an undergraduate environmental law class to students at Boston College.
  • Mr. Cosmas served two terms as President of the Georgetown Club of Greater Boston, the university's official alumni club in Massachusetts, from 2011-2015. He also served as an assistant coach for a Beverly Youth Soccer Association Under-8 girls soccer team for two years, until his daughter discovered competitive dancing.

Teaching and Publications

Cases of Note

  • Successfully represented property owner in boundary and property dispute with downhill abutting property owner in Land Court; case resolved by settlement.
  • Assisted in successful opposition to motion to compel brought by Hatch-Waxman plaintiff against client, a non-party, then-publicly traded clinical research organization (United Therapeutics Corp. v. Watson Labs., Inc., 200 F.Supp.3d 272 (D. Mass. 2016)).
  • Successfully represented hotel proprietor in construction arbitration against former general contractor; compelled contractor to arbitrate under Massachusetts Arbitration Act; matter resolved through mediation prior to arbitration hearing.
  • Successfully represented international industrial materials company and its owner in parallel employment and breach of contract disputes against former employee, both disputes resolved through mediation.
  • In a 2014 pro bono matter, successfully represented petitioner for clemency in Massachusetts, obtaining one of the first pardons in the Commonwealth since 2002.
  • Assisted in successful defense of government contractor in two-year long criminal false claims and environmental investigation by the Massachusetts Attorney General’s Office, ultimately resolved by a civil settlement.
  • Assisted in successful representation of seed investors in breach of contract and fiduciary duty litigation against hedge fund manager; settlement reached after jury empaneled.

Professional Activities and Associations

  • Member, Boston Bar Association
  • Member Massachusetts Bar Association
  • Admitted to Massachusetts state bar, the United States District Court for the District of Massachusetts, and the Court of Appeals for the First Circuit.
  • Super Lawyers
  • Best Lawyers | 2020
  • Preeminent AV | LexisNexis Martindale-Hubbell Peer Review Rated For Ethical Standards and Legal Ability