Ann Marie Duffy

Partner

T 202.898.5834

Ann Marie Duffy is an accomplished trial lawyer who has broad experience in the defense of complex civil litigation. With over twenty years of experience, she has represented companies in some of their most significant cases on a variety of claims, including commercial disputes, construction claims, products liability, environmental tort, fraud, and intellectual property claims.

Ann Marie has successfully tried cases to verdict or obtained judgment for her clients in courts throughout the U.S.  In addition to trying commercial disputes, Ann Marie has tried cases involving trademark and patent infringement claims as well as cases involving alleged injury from exposure to a variety of chemicals, including PFAS and ethylene oxide.

Currently, Ann Marie is lead counsel for several firm clients across a variety of cases, including a PFAS manufacturer defending against claims of negligence, personal injury, and natural resource damages in several states; She is also lead counsel for a producer of PTFE and silicone coated fabrics, tapes, and belts, defending against claims of negligence, trespass, and nuisance for its use and handling of materials containing trace amounts of PFOA; and for a manufacturer of talc-containing products facing claims of alleged injury from asbestos exposure. Ann Marie is a trial team partner in another major natural resource damages case involving claims of negligence and ecological harm in which the state is seeking hundreds of millions of dollars in economic compensation and primary restoration. She is also a trial team partner defending a major engineering firm in Arkansas Circuit Court against alleged breach of contract, professional negligence, and fraud claims arising from the design, engineering, and construction of a nearly $1 billion agrochemical plant.

In addition to her trial experience, Ann Marie has briefed and argued appeals to the United States Court of Appeals for the District of Columbia Circuit, the United States Court of Appeals for the Tenth Circuit, and the State of New York Supreme Court, Appellate Division Third Judicial Department.

Education

George Washington University Law School (J.D., 2002) James Madison University (B.A., 1999, cum laude)

Admissions

  • District of Columbia
  • Virginia
  • United States Supreme Court
  • United States Court of Appeals for the District of Columbia Circuit
  • United States Court of Appeals for the Federal Circuit
  • United States District Courts for the District of Maryland, Western District of Tennessee, Eastern District of Texas, and Eastern and Western Districts of Virginia
  • Supreme Court of Virginia
  • District of Columbia Court of Appeals

Accolades

  • Chambers USA
    • “Ann Marie Duffy at Hollingsworth LLP is a very strategic thinker. She is able to stitch together complicated factual and documentary themes in litigation. She was excellent in trial with witnesses, arguing motions to court, and opening and closing arguments. She is an excellent trial lawyer, confident before the jury, and very credible.” — Client
    • “Ann Marie Duffy’s client service, level of sophistication, and commercial vision [are] 10 out of 10. She has counseled us on critical litigation. Her advice has been extremely useful.” — Client
    • “Ann Marie Duffy at Hollingsworth LLP is an outstanding lawyer. She is very smart and creative.” — Third Party
    • “Ann Marie Duffy — I have nothing but good things to say about her leadership. She is getting the team heading in the right direction.” — Client
    • “Ann Marie is practical, and she gives good advice.” — Client
  • Super Lawyers, Business Litigation, 2023-2026
  • 2023 Annual M&A Advisor Awards Winner “Professional Services Deal of the Year”, Deal Team Member

Memberships

  • Sustaining Member, PLAC
  • Serves as General Counsel to the National Catholic Forensic League (a nonprofit hosting speech and debate activities for the secondary school community to encourage and assist in the development of articulate leaders)
  • Member, National Catholic Forensic League, since 2007
  • Member, Washington-Arlington Catholic Forensic League (hosting speech and debate activities in the greater Washington, DC metro area)

Insights & Events

Cases