NBA champion Boston Celtics to be sold for a record US$6.1 billion to group led by Bill Chisholm

Boston Celtics forward Jayson Tatum (0) drives to the basket against Brooklyn Nets forward Ziaire Williams (8) during the first half of an NBA basketball game, Saturday, March 15, 2025, in New York. (AP Photo/Noah K. Murray)

The Boston Celtics are being sold for what would be a record-setting initial valuation of $6.1 billion to a group led by Symphony Technology Group managing partner William Chisholm, the sides said Thursday.

The sale -- if approved by the NBA’s board of governors after a thorough vetting process -- would be the richest in U.S. major pro sports history. That process likely would not be completed until the summer, at the earliest.

The $6.1 billion valuation -- which would seem to be a minimum, since that is just the initial number -- would break the mark set when a group led by Josh Harris bought the NFL’s Washington Commanders for $6.05 billion in 2023. Sportico and ESPN were among those first reporting the agreement for the sale of the reigning NBA champions.

Boston Basketball Partners LLC announced last summer that it intended to sell the majority of the Celtics either late last year or early this year, then would sell the balance of its shares in 2028. Wyc Grousbeck, whose family leads the ownership group, is expected to remain the Celtics' governor through the 2027-28 season.

Grousbeck’s group bought the Celtics for $360 million in 2002.

“My partners and I have immense respect for Wyc, the entire Grousbeck family and their indelible contributions to the Celtics organization over the last 23 years,” Chisholm said in a release announcing the agreement, the details of which were confirmed by the agencies representing both sides involved in the sale. “We look forward to learning from Wyc and partnering with Brad Stevens, Joe Mazzulla and the talented team and staff to build upon their success as we work to bring more championships home to Boston.”

The $6.1 billion figure would also top -- by a big margin -- recent NBA franchise sales. In 2023, the Phoenix Suns were purchased by mortgage firm owner Mat Ishbia for $4 billion, the Milwaukee Bucks were sold to Cleveland Browns owners Jimmy and Dee Haslam for $3.5 billion, and Mark Cuban agreed to the sale of the majority of his Dallas Mavericks' ownership shares to Miriam Adelson and son-in-law Patrick Dumont, who operates the Las Vegas Sands casino company, for $3.5 billion.

“Bill is a terrific person and a true Celtics fan, born and raised here in the Boston area,” Grousbeck said. “His love for the team and the city of Boston, along with his chemistry with the rest of the Celtics leadership, make him a natural choice to be the next governor and controlling owner of the team.”

Grousbeck added that Chisholm “asked me to run the team as CEO and governor for the first three years, and stay on as his partner.”

“I am glad to do so,” Grousbeck said.

By Tim Reynolds