John J. O

John J. O'Neil

Listed in Best Lawyers since 1995

Of counsel in the Personal Representation Department, John (Jack) O'Neil concentrates in international and domestic estate planning, trusts and estates administration and related tax work, matrimonial matters including divorce and premarital agreements, private foundations and planning for partnerships and closely held corporations.

Additional Information


Jack is a trusted counselor for individuals and families of very high net worth, many of whom are clients that he has represented for decades. He also has experience representing the development offices of two major medical centers and a large number of family offices. His experience includes:

  • counseling high net worth domestic and international family offices and individuals on various wills, trusts, estate planning, matrimonial and financial matters;
  • representing one of the world's oldest and largest cancer centers for 30 years regarding its estate, trust and major gift matters;
  • representing a major corporate fiduciary in a highly visible and heavily contested matter regarding a multimillion dollar estate administration and tax audits; and
  • serving as a fiduciary on dozens of matters in active administration.
University of Virginia School of LawJ.D. 1968

Office Location

1285 Avenue of the Americas
New York, NY 10019-6064
United States

Practice Areas

Trusts and Estates