Daniel R. Sonneborn is a Director in the firm's Litigation Practice Group, working primarily from the firm’s Boston office. A negotiator and litigator, his clients include those in professional services and regulated industries like transportation, insurance, health care, financial services, and construction. Dan’s counsel ranges in focus from professional liability and risk mitigation to multi-jurisdictional class actions. He has developed a particular interest in transportation law, and represents motor carriers, brokers, freight forwarders, and insurance companies in transportation-related matters and litigation, including cargo loss and damage, warehousing, contractual issues, and employment matters.

Despite his upbringing in a family of medical providers, Dan found his professional path in law school, where he was able to combine his generational connection to medicine with his passion for problem-solving. He served as Managing Editor of Suffolk Law’s Journal of Health and Biomedical Law, and continues to advise healthcare professionals to this day. His deep New England roots are reflected in his experience appearing in state and federal courts in Massachusetts, Maine, and New Hampshire.  

Dan lives in Medford, Massachusetts, with his wife and two children.

Professional Activities

  • Massachusetts Defense Lawyers Association
  • Transportation Lawyers Association
  • Conference of Freight Counsel

Honors & Recognition

  • Massachusetts Super Lawyers Rising Star, Transportation/Maritime – 2016 - 2021

Civic and Charitable Activities

  • Coach, Medford Youth Hockey and Baseball


  • Co-author, Introduction, A Practical Guide to Understanding RSA 358-A in New Hampshire (MCLE New England, 1st Edition, 2014).