Who is William Chisholm? Biography, Net Worth, and Key Details

In a groundbreaking transaction, William Chisholm, backed by private equity powerhouse Sixth Street, has reached an agreement to acquire the Boston Celtics, marking the most expensive team sale in NBA history. The deal, structured in two phases, is valued at an initial $6.1 billion, with a blended valuation of $6.6 billion, surpassing the previous record set by Mat Ishbia’s $4 billion purchase of the Phoenix Suns.

A Strategic Two-Phase Acquisition

Chisholm, the managing partner of Symphony Technology Group (STG), orchestrated this acquisition in alignment with the current ownership’s multi-stage exit strategy. The Grousbeck family, which has controlled the Celtics since 2002, emphasized a phased transition, with the first sale segment transferring 51% ownership. Wyc Grousbeck will retain control as team governor until the final phase in 2028.

In a letter to Celtics investors, Wyc and Irving Grousbeck confirmed the sale and acknowledged the strong competition among bidders.

“This was an extremely thorough, rigorous sale process,” the letter stated. “We had tremendous interest from potential control owners, and we’re grateful for the considerable time and effort bidders put in over the past few months. In the end, Bill and his group came in with a superior final bid.”

Key Players in the Acquisition

The Chisholm-led consortium boasts a formidable lineup of financial and sports industry figures, including:

• Sixth Street, a global investment firm contributing over $1 billion to the deal.
• Rob Hale, a current Celtics investor.
• Bruce A. Beal Jr., president of Related Companies.

Sixth Street, which manages over $100 billion in assets, has an extensive sports investment portfolio, including:

• Minority stakes in the San Antonio Spurs, Real Madrid, and FC Barcelona.
• Ownership of Legends and NWSL’s Bay FC.

With this move, Sixth Street joins a growing list of private equity firms investing in multiple NBA teams, alongside Arctos Partners (Warriors, 76ers, Kings, Jazz) and Blue Owl (Hawks, Timberwolves, Kings).

What This Means for the Celtics and the NBA

The Boston Celtics, a historic franchise and 18-time NBA champions, have long been one of the league’s most valuable and recognizable teams. Despite their strong brand and global fan base, they do not own their arena and hold only a small stake in their local media partner, raising questions about their long-term revenue potential.

The sale, however, sets a new financial benchmark for NBA franchise valuations. Industry analysts speculated whether the Celtics would surpass the $6 billion mark, and this deal confirms that NBA team values continue to soar.

The Grousbeck Legacy and the Road Ahead

The Grousbeck-led group acquired the Celtics in 2002 for $360 million, meaning their return on investment exceeds 1,600%. Their decision to sell stemmed from estate planning considerations, with Irving Grousbeck, now nearly 90 years old, seeking a structured transition.

While Chisholm and his new ownership group will take immediate control of operations, Wyc Grousbeck remains in charge through 2028, ensuring stability and continuity for the franchise.

Finalizing the Sale

The Celtics’ sale process, managed by BDT & MSD and JPMorgan Chase, attracted several high-profile bidders, including:

• Stan Middleman, owner of the Philadelphia Phillies.
• The Friedkin Group.
• Steve Pagliuca, an existing Celtics investor and previously considered a front-runner.

Ultimately, Chisholm’s bid outpaced all competitors, securing his place as the future steward of one of the NBA’s most storied franchises.

With this record-breaking deal, the Boston Celtics enter a new era, one defined by private equity investment, financial expansion, and heightened league valuations—all while staying committed to their championship ambitions