Grousbeck’s partners would include: Mark Wan, a managing director with healthcare-focused VC firm Three Arch Partners who also is a minority owner in both the Celtics and San Francisco 49ers; and Bob Higgins, a Highland Capital Partners co-founder who has been cutting back his responsibilities with the Boston-area firm.

No details yet on the specific investment strategy, or if the trio is planning to raise outside capital. There are no indications, however, that Grousbeck plans to give up his day job running the 17-time NBA champs.

Wyc Grousbeck spent seven years working at Highland Capital Partners, before leaving in 2002 to purchase the Celtics along with his father Irving Grousbeck, Bain Capital’s Steve Pagliuca, Abbey Group’s Bob Epstein and a large group of limited partners (mostly from the VC and private equity worlds). He is the ownership group’s most involved member on a day-to-day basis, although he briefly returned to Highland in 2006 as a venture partner.

Grousbeck and Wan declined to comment, while Higgins did not return messages left by Fortune.

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