Nathaniel Chiaravalloti is an Associate with Marks, O’Neill, O’Brien, Doherty & Kelly’s New York City office.  He is admitted to practice in New York, as well as the Eastern and Southern Federal District Courts.  He is also a member of the New York Bar Association and New York County Lawyers Association.

Nathaniel graduated from Iowa State University in 2008, with a Bachelor of Arts in Political Science. After serving in the AmeriCorps programs, he then attended St. John’s University School of Law, graduating in 2014.  During law school, Nathaniel was the Senior Articles Editor for the Journal of Civil Rights and Economic Development, President of the Admiralty Law Society and Editor-in-Chief of the Forum, the newspaper of St. John’s University School of Law. Also, Nathaniel worked as an intern for Justice James Catterson, in the Appellate Division, First Department in New York City.  Notably, he competed in the International Academy of Dispute Resolution’s Law School Mediation Tournament in Dublin, Ireland, where he was honored as First Place – Advocate/Client team.

Since joining Marks O’Neill in 2016, Nathaniel has represented clients in toxic and environmental torts, premises liability, nuisance and general liability matters.  He focuses his practice in toxic and environmental tort. He has extensive experience with motion practice, trial work, evaluating liability and examining witnesses before trial.

Nathaniel enjoys movies, politics, live music and Muay Tai kickboxing.  Originally from Davenport, Iowa, he lives with his wife and cats in Astoria, Queens.

Nathaniel Chiaravallotti
Associate / New York City

Phone 646-454-4884

Nathaniel Chiaravallotti PDF


  • J.D., St. John’s University School of Law, 2014
  • B.A., Iowa State University, 2008

Bar Admissions

  • New York
  • U.S. District Court for Southern District, New York
  • U.S. District Court for Eastern District, New York

Bar Associations

  • New York Bar Association
  • New York County Lawyers Association

Practice Areas

  • Casualty Group
  • Toxic Tort, Mass Tort, Environmental and Products Liability


New York City
708 Third Avenue, Suite 2500, New York, NY 10017