William J. Kambas

Partner | Greenwich, New Haven, New York

Bill is a partner in the private client and tax team.

He focuses on tax planning for multi-national and multi-state personal, active business, and investment activities, with a particular emphasis on tax structuring and choice of business entity for US and non-US business owners and investors. Bill has represented a wide variety of private and public businesses, including family-owned, start-ups and multi-million dollar enterprises on purely domestic as well as inbound and outbound business transactions, cross-border investments (whether made directly or through investment funds or joint ventures), and qualification for US tax treaty benefits. In particular, he has considerable experience advising non-US persons on the US income and estate tax consequences and tax planning associated with the ownership of US real estate (whether residential or commercial, developmental, operational, or for personal use).

An integral part of Bill’s work involves working assisting families, their family offices, and/or family enterprises with the formation, management, and/or periodic evaluation of multinational and/or multi-generational centralized control and management structures.

Secretary Mary Marshall





State of Connecticut, 2003

State of New York, 2004

United States Tax Court, 2004

‘How U.S. Persons Can Be Made Public by the UK Register,’ Estate Planning - August 2017, co-author

"New York Banking Royalty’s Heirs Are Unloading Art to Save the Family Estate," Bloomberg, April 2017, quote

Skidmore College Annual Fund

Saint Barbara Greek Orthodox Church Endowment Fund

‘Interactive round table discussion’, STEP International Estate Planning Conference Wyoming - 15-16 September, moderator

‘Greek Family Firms: Exploring the Logic and Dynamics of the International Shipping Enterprise’ Yale University, The MacMillan Center, Hellenic Studies Program, with Elian Kulukundis, May 2017

‘Encouraging Engaged Ownership through Legal Architecture,’ International Association of Attorneys for Family-Held Enterprises ("AFHE"), Miami, FL, April 27. 2017



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1700 East Putnam Avenue,

Suite 400,

CT 06870-1366

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New Haven

157 Church Street,

CT 06510-2100

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New York

430 Park Avenue,

10th Floor,

NY 10022-3505

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