How Bill built the fortune
Bill Ackman is an activist investor. His method is to buy large stakes in a small number of public companies and then push management, sometimes publicly and forcefully, to change strategy, sell divisions, replace executives or return capital. Pershing Square Capital Management, which he founded in 2004 after the wind down of his first fund, runs a concentrated portfolio of often fewer than a dozen positions.
Several campaigns made large profits. Pershing Square pressed for change at Canadian Pacific Railway, backed a new chief executive and earned a large gain. It invested successfully in restaurant chains including Chipotle and in Hilton, and in early 2020 Ackman bought credit protection as a hedge just before pandemic panic hit markets, turning a small outlay into a gain of about 2.6 billion dollars. As founder and principal owner of the firm, Ackman shares in fees and performance and has kept much of his own money invested in its funds.
There were also costly failures. A multi-year short bet against Herbalife ended in losses, and a large position in Valeant Pharmaceuticals collapsed in 2015 and 2016. Those setbacks shrank the firm's assets for several years before a strong recovery.
His approach depends on conviction. Pershing Square often explains its theses in long public presentations, letters and interviews, which can move share prices and rally other shareholders behind its demands. That openness has helped the firm win board seats and strategic changes, but it also makes its mistakes highly visible. Ackman has acknowledged several errors publicly, and after the Valeant losses he narrowed the firm's focus toward simple, predictable businesses with strong brands and pricing power.
Companies and holdings
Ackman's main business interests include:
- Pershing Square Capital Management, the investment adviser he founded and leads
- Pershing Square Holdings, a permanent capital fund listed in Amsterdam since 2014, and later also in London
- Howard Hughes Holdings, a real estate developer in which Pershing Square holds a large stake and where Ackman has served as chairman
- the Pershing Square Foundation, his charitable vehicle
In 2020 he launched Pershing Square Tontine Holdings, at the time the largest special purpose acquisition company ever listed. A planned deal for a stake in Universal Music Group was restructured, and the vehicle eventually returned its money to investors without completing a merger.
In recent years Ackman has also explored taking his asset management business into new directions, including plans for a listed closed-end fund in the United States, which was postponed in 2024, and continued expansion of Howard Hughes into a broader holding company modelled loosely on Berkshire Hathaway.
Early life and career
Ackman was born in 1966 and grew up in Chappaqua, New York, where his father ran a commercial real estate finance firm. He studied at Harvard College, graduating in 1988, and returned to Harvard for an MBA, which he completed in 1992.
Straight after business school he co-founded Gotham Partners with classmate David Berkowitz. Gotham made early activist investments but ran into trouble around 2002 with illiquid holdings and a dispute over a golf course company, and it was eventually wound down. Ackman used that experience in designing Pershing Square, which he launched with backing from Leucadia National and other investors.
Philanthropy and public life
Ackman established the Pershing Square Foundation in 2006 and signed the Giving Pledge. The foundation has funded medical research, education, economic development and social entrepreneurship, and has made large grants to institutions in New York and elsewhere. He has also supported programs at Harvard and in Israel.
Ackman is a very active public commentator, especially on the social media platform X, where he writes at length about markets, politics and higher education. In late 2023 he led a high profile campaign criticizing Harvard's leadership over its response to antisemitism on campus, which contributed to the resignation of the university's president. His outspokenness has made him one of the most widely followed figures on Wall Street outside the investment community. He has also donated to medical research on a range of diseases through grants made by his foundation.