Sean R. Weissbart



Sean R. Weissbart concentrates his practice in the areas of trusts and estates law and tax-exempt organizations.

His trusts and estates practice is focused on domestic and international estate planning, the administration of trusts and estates, and the representation of beneficiaries and fiduciaries in contested matters in Surrogate’s Court. He also advises clients on the negotiation of pre- and post-nuptial agreements and the modification of trusts upon divorce.

Sean also counsels tax-exempt organizations on matters ranging from formation and obtaining of tax-exempt status from the Internal Revenue Service (“IRS”) to complying with state and federal tax-exemption laws and the avoidance of excise taxes and the unrelated business income tax. He has also litigated against the IRS in United States federal courts.

Sean serves as an adjunct professor of law at New York University School of Law, where he teaches Income Taxation of Trusts and Estates and International Estate Planning. He is a fellow of The American College of Trust and Estate Counsel, a national organization of trusts and estates attorneys who have demonstrated the highest level of professionalism in the field. He also serves on the boards of various philanthropic organizations, including as general counsel to the Ment’or BKB Foundation, an organization that sponsors the American team at the Bocuse d’Or (a biannual culinary competition in France), and as chair of the “NextGen” Trusts and Estates Committee of the UJA Federation of New York.

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  • 2023–2024, Trusts and Estates in New York, listed in Best Lawyers in America©
  • 2015–Present, “Rising Star” in Estate Planning and Tax-Exempt Organizations, listed by Super Lawyers
  • 2022–2023, “Up and Coming” for New York Private Wealth Law: Mid-Market, listed in Chambers High Net Worth
  • 2010, “Justice Award” for Outstanding Contributions to Pro Bono Legal Services in New York City, awarded by MFY Legal Services



  • New York
  • U.S. District Court - Eastern District of New York
  • U.S. District Court - Southern District of New York
  • United States Court of Federal Claims


  • New York University, BA, magna cum laude
  • Fordham University School of Law, JD
  • New York University School of Law, LLM