About Joseph Darby

Joseph B. Darby is a tax attorney and has more than 27 years of experience, specializing in business and transactional tax law.

As a partner in Sullivan & Worcester's Boston office, Darby represents companies and high net worth individuals in tax, corporate, financial, real estate and estate planning transactions.

Darby also focuses on Qualified Opportunity Funds and Opportunity Zone businesses. He has helped to form several Qualified Opportunity Funds ranging from small private deals to transactions in the $200 million to $500 million range. Another focus of Darby’s practice is the taxation of intellectual property, including the development, licensing and exploitation of intellectual property rights.

Before joining Sullivan & Worcester in 2013, Darby was an attorney with Greenberg Traurig in Boston for 13 years. Previously, he also worked for Sherburne, Powers & Needham for eight years, also in Boston. Darby has done pro bono work for several Boston-area charitable organizations, and serves as president of the Watertown Police Foundation, Inc., which he formed in 2013 after the Boston Marathon bombing to support local law enforcement efforts and help the community recover.

In addition to practicing tax law, Darby is also a writer. He has received numerous awards in both fields. He has been recognized by Best Lawyers in America, Legal 500 U.S., and Tax Writer of the Year, World Trade Executive, Inc., a division of Thomson Reuters.

Darby earned a Juris Doctor from Harvard Law School. He received his bachelor’s degree at the University of Illinois at Urbana-Champaign. Darby is admitted to practice law in Massachusetts and the U.S. Tax Court.


Sullivan & Worcester LLP


One Post Office Square, Boston



OZ Verified

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  • Active BAR member in good standing
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  • The state of the OZs examined in two national reports

    July 20, 2020

    Two significant reports on Opportunity Zones were issued within hours of each other by two important organizations, the White House Opportunity and Revitalization Council and the Urban Institute, on June 17.