# Bill Chisholm (businessman)
**William "Bill" Chisholm** is an American private equity investor, co-founder, managing partner, and chief investment officer of STG (formerly Symphony Technology Group), a [Silicon Valley](https://www.edgepedia.org/silicon-valley) software-focused buyout firm, and since 2025 the controlling owner and governor of the [Boston Celtics](https://www.edgepedia.org/boston-celtics), which his group bought for a record $6.1 billion.[1](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0) • [2](https://apnews.com/article/boston-celtics-sale-c8d050f615af7563c71ffe1f7601825d)
| Key fact | Detail |
|---|---|
| Firm | Co-founded STG in 2002 with software billionaire Romesh Wadhwani; Menlo Park, California; data, software, and analytics investing[1](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0) |
| Fund scale | Nearly $10 billion raised across funds and more than 100 investments as of 2023; seventh and largest fund closed in 2023 at $4.2 billion[1](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0) |
| Celtics deal | $6.1 billion initial valuation, the largest price ever for an American professional sports team; two-part sale with full control by 2028[2](https://apnews.com/article/boston-celtics-sale-c8d050f615af7563c71ffe1f7601825d) |
| Approval | NBA board of governors approved unanimously; Chisholm's fully funded bid was approved in August 2025, five months before his December 31 funding deadline[3](https://www.nba.com/news/chisholm-group-celtics-ownership) • [4](https://www.bostonglobe.com/2025/12/17/sports/bill-chisholm-celtics-owner/) |
| Education | B.A. from Dartmouth College; MBA in strategic management from the Wharton School, 1996[1](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0) |
| Early career | Investment banker at PaineWebber; manager at Bain & Co., where he co-founded Bain Ventures; founding partner of The Valent Group[5](https://aletteraday.substack.com/p/letter-272-bill-chisholm-2014) |
| Net worth | Forbes estimates greater than $1 billion[6](https://www.forbes.com/profile/william-chisholm/) |
## Early life, education, and early career
Chisholm is a Massachusetts native and a [Dartmouth College](https://www.edgepedia.org/dartmouth-college) graduate who received an MBA in strategic management from the [Wharton School](https://www.edgepedia.org/wharton-school) in Philadelphia in 1996.[1](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0) He started his career as an investment banker at PaineWebber, then became a manager at the consulting firm Bain & Co., where he co-founded Bain Ventures and founded and served as president of Servicys, a supply chain software and services company.[5](https://aletteraday.substack.com/p/letter-272-bill-chisholm-2014) Before Symphony he was a founding partner of The Valent Group, a joint venture fund between Accel Partners and [Bessemer Venture Partners](https://www.edgepedia.org/bessemer-venture-partners) focused on enterprise software.[5](https://aletteraday.substack.com/p/letter-272-bill-chisholm-2014) • [7](https://www.sportico.com/business/team-sales/2025/bill-chisholm-celtics-sale-6-1-billion-1234843982/)
## Symphony Technology Group: founding and model
STG grew out of a family office. Tech billionaire [Romesh Wadhwani](https://www.edgepedia.org/romesh-wadhwani) sold his e-commerce software firm Aspect Development for more than $9 billion in 2000 and initially opened Symphony to oversee his own investments; Chisholm joined as a co-founder in 2002.[8](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/) The firm, based in [Menlo Park, California](https://www.edgepedia.org/menlo-park-california), specializes in technology investing, particularly data, software, and analytics companies.[1](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0)
**Long-hold carve-outs.** Symphony typically holds companies longer than most buyout firms, sometimes 10 years or more, and often spends a few hundred million dollars per deal rather than billions.[8](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/) By 2023 it had raised nearly $10 billion across its private equity funds and completed more than 100 investments, closing its seventh and largest fund that year at $4.2 billion.[1](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0) Sportico put the portfolio at more than 50 active and closed investments with about $10 billion of assets under management as of March 2023,[7](https://www.sportico.com/business/team-sales/2025/bill-chisholm-celtics-sale-6-1-billion-1234843982/) while Forbes describes STG Partners as a software-focused Silicon Valley firm with about $12 billion in assets; the two figures have not been reconciled.[6](https://www.forbes.com/profile/william-chisholm/)
## Investment track record and criticisms
Chisholm serves as STG's managing partner and chief investment officer, and the firm's signature deals show the long-hold model's returns. It bought First Advantage, a background-check software maker, in 2010 for $265 million and sold it to Silver Lake in 2019 for a reported $1.5 billion; it bought MSC Software for $360 million in 2009 and sold it in 2017 for $834 million.[8](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/) It bought Shopzilla for $165 million in 2011 (E.W. Scripps had paid $525 million in 2005) and sold the renamed Connexity to Taboola for $800 million in 2021.[8](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/) In an early deal, Chisholm bought a struggling company that scraped data from UPC codes for about $100 million and sold it for nearly $1 billion about six years later.[4](https://www.bostonglobe.com/2025/12/17/sports/bill-chisholm-celtics-owner/)
**Larger deals.** In 2020 Symphony led a group that bought the encryption pioneer RSA from Dell for $2.1 billion; in 2021 it paid $4 billion for part of McAfee's cybersecurity business, and during Chisholm's tenure STG combined McAfee Enterprise and FireEye to create the cybersecurity company Trellix in 2022.[8](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/) • [1](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0) It also acquired [Momentive](https://www.edgepedia.org/momentive), the parent of [SurveyMonkey](https://www.edgepedia.org/surveymonkey), in a purchase [Business Insider](https://www.edgepedia.org/business-insider) puts at $1.5 billion,[9](https://www.businessinsider.com/who-is-bill-chisholm-boston-celtics-stg-2025-3) and in 2023 it bought Avid Technology, maker of media-editing software such as Pro Tools, for $1.4 billion.[8](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/) • [9](https://www.businessinsider.com/who-is-bill-chisholm-boston-celtics-stg-2025-3)
The main documented criticism of the model is job cutting after acquisitions: after the Avid purchase, STG cut an undisclosed number of jobs at the company.[8](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/)
## Purchase of the Boston Celtics
On the March 14, 2025 deadline, Chisholm submitted his final bid at an initial valuation of $6.1 billion, outbidding at least two other groups, one led by current Celtics minority partner Steve Pagliuca.[4](https://www.bostonglobe.com/2025/12/17/sports/bill-chisholm-celtics-owner/) • [2](https://apnews.com/article/boston-celtics-sale-c8d050f615af7563c71ffe1f7601825d) The agreement calls for a two-part sale in which Chisholm would acquire at least 51% of the team upon approval by the NBA's board of governors, with current owners able to retain the remainder until 2028, when those shares would be sold at a price up to 20% higher based on a formula determined by league revenue growth.[2](https://apnews.com/article/boston-celtics-sale-c8d050f615af7563c71ffe1f7601825d) The sides agreed Chisholm would have until December 31 to fully fund the transaction, with a break-up fee he described as "several hundred million dollars" if he could not; his fully funded bid was approved by the NBA in August 2025, five months early, and the money changed hands after the league's unanimous approval.[4](https://www.bostonglobe.com/2025/12/17/sports/bill-chisholm-celtics-owner/) • [3](https://www.nba.com/news/chisholm-group-celtics-ownership)
The NBA approved the deal unanimously, calling it a record price for an American professional sports franchise.[3](https://www.nba.com/news/chisholm-group-celtics-ownership) The investor group includes Boston businessmen Rob Hale, a current Celtics shareholder, and Bruce Beal Jr.[2](https://apnews.com/article/boston-celtics-sale-c8d050f615af7563c71ffe1f7601825d) Chisholm represents the team in league matters as governor, with seller [Wyc Grousbeck](https://www.edgepedia.org/wyc-grousbeck) staying on as co-owner, CEO, and alternate governor to run day-to-day operations alongside him; team president Rich Gotham, general manager [Brad Stevens](https://www.edgepedia.org/brad-stevens), and coach [Joe Mazzulla](https://www.edgepedia.org/joe-mazzulla) are all expected to remain.[3](https://www.nba.com/news/chisholm-group-celtics-ownership)
## How it compares with other franchise sales
The $6.1 billion price is the largest ever for an American professional sports team and, at a blended valuation of about $6.6 billion, by far the most ever paid for control of an NBA team, eclipsing the $4 billion valuation when [Mat Ishbia](https://www.edgepedia.org/mat-ishbia) bought the [Phoenix Suns](https://www.edgepedia.org/phoenix-suns).[2](https://apnews.com/article/boston-celtics-sale-c8d050f615af7563c71ffe1f7601825d) • [7](https://www.sportico.com/business/team-sales/2025/bill-chisholm-celtics-sale-6-1-billion-1234843982/) Sportico had valued the Celtics at $5.66 billion before the sale.[7](https://www.sportico.com/business/team-sales/2025/bill-chisholm-celtics-sale-6-1-billion-1234843982/) For the sellers, the appreciation is steep: Grousbeck's group paid $360 million for the team in 2002 and is making almost 17 times its initial purchase price.[8](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/)
## Recent developments
The period from 2023 to late 2025 took Chisholm from closing STG's largest fund to the largest deal in American sports. In 2023 STG closed its $4.2 billion seventh fund and bought Avid Technology for $1.4 billion, later cutting jobs there.[1](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0) • [8](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/) In March 2025 he won the Celtics bidding; in August the NBA approved his fully funded bid; and the transaction closed with him holding majority ownership control, with full control coming by 2028.[4](https://www.bostonglobe.com/2025/12/17/sports/bill-chisholm-celtics-owner/) • [3](https://www.nba.com/news/chisholm-group-celtics-ownership) On the court, the Celtics, projected to carry an NBA-record salary and luxury-tax bill of about $540 million for the 2025–26 season, shed about $300 million with the departures of veterans such as Al Horford, Kristaps Porzingis, and Jrue Holiday under the new ownership.[4](https://www.bostonglobe.com/2025/12/17/sports/bill-chisholm-celtics-owner/)
## By the numbers
- Celtics initial valuation: $6.1 billion; blended valuation about $6.6 billion; the deferred 2028 purchase would value the team at $7.3 billion under AP's account, while the Boston Globe reports the valuation rising to approximately $6.6 billion when the second part closes in 2028; both figures are reported here as published.[2](https://apnews.com/article/boston-celtics-sale-c8d050f615af7563c71ffe1f7601825d) • [7](https://www.sportico.com/business/team-sales/2025/bill-chisholm-celtics-sale-6-1-billion-1234843982/) • [4](https://www.bostonglobe.com/2025/12/17/sports/bill-chisholm-celtics-owner/)
- STG: nearly $10 billion raised across funds, more than 100 investments, $4.2 billion seventh fund (2023); about $10 billion AUM per Sportico versus about $12 billion in assets per Forbes.[1](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0) • [7](https://www.sportico.com/business/team-sales/2025/bill-chisholm-celtics-sale-6-1-billion-1234843982/) • [6](https://www.forbes.com/profile/william-chisholm/)
- Celtics appreciation under the sellers: $360 million in 2002 to $6.1 billion in 2025, almost 17 times.[8](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/)
- Payroll: about $540 million projected salary and luxury tax for 2025–26, about $300 million shed in departures.[4](https://www.bostonglobe.com/2025/12/17/sports/bill-chisholm-celtics-owner/)
## References
1. [Who is Bill Chisholm, leader of the group that bought the Celtics for $6.1B? | AP News](https://apnews.com/article/basketball-nba-celtics-boston-dba407c483edad0492b88e644ffcaba0)
2. [NBA's Celtics to be sold for record $6.1 billion to group led by private equity mogul Bill Chisholm | AP News](https://apnews.com/article/boston-celtics-sale-c8d050f615af7563c71ffe1f7601825d)
3. [Chisholm group takes over ownership control of Celtics | NBA.com](https://www.nba.com/news/chisholm-group-celtics-ownership)
4. [How Boston Celtics owner Bill Chisholm closed the wildest deal of his life | The Boston Globe](https://www.bostonglobe.com/2025/12/17/sports/bill-chisholm-celtics-owner/)
5. [Letter #272: Bill Chisholm (2014) | A Letter a Day](https://aletteraday.substack.com/p/letter-272-bill-chisholm-2014)
6. [William Chisholm | Forbes](https://www.forbes.com/profile/william-chisholm/)
7. [William Chisholm to Buy Boston Celtics in $6.1 Billion Deal | Sportico](https://www.sportico.com/business/team-sales/2025/bill-chisholm-celtics-sale-6-1-billion-1234843982/)
8. [William Chisholm: Celtics buyer made money in private equity | The Boston Globe](https://www.bostonglobe.com/2025/03/21/business/william-chisholm-celtics-money/)
9. [Who Is Bill Chisholm, the New Owner of the Boston Celtics? | Business Insider](https://www.businessinsider.com/who-is-bill-chisholm-boston-celtics-stg-2025-3)
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*Topic: Encyclopedia › Society and history › Economics and business › Finance › People in finance › Investors and fund managers › Private equity and buyout investors*
*Initially written Sep 17, 2026 · Reviewed: Sep 30, 2026; Oct 10, 2026 · Edited: Oct 10, 2026; Oct 11, 2026; Oct 15, 2026 · Last review: Oct 10, 2026*
*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*
License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license