Billionaire investor Bill Ackman is experiencing an extraordinary year, with his net worth rocketing to an estimated $9.2 billion in 2025, a significant increase from $4.3 billion in 2024, according to Forbes. This remarkable surge is directly attributable to the exceptional performance of his hedge fund, Pershing Square Capital Management, and its primary investment vehicle, Pershing Square Holdings.

Pershing Square Holdings, a London-listed closed-end fund also traded on OTC Markets under the ticker PSHZF, has demonstrated outstanding returns. So far in 2025, the fund has delivered a 25.3% return, vastly outperforming the S&P 500’s 11.7% total return over the same period. The fund’s net asset value (NAV) is reported weekly and currently stands at approximately $16 billion, while its market value is around $11 billion.

The stellar performance has been predominantly fueled by the fund's substantial and highly profitable holdings in mortgage giants Fannie Mae and Freddie Mac. Reports indicate that Pershing Square has generated an estimated profit of roughly $2 billion from these specific investments alone in 2025.

Both Fannie Mae and Freddie Mac shares have witnessed an explosive rally throughout 2025. Fannie Mae closed at $14.64, marking an impressive 350% increase since January, while Freddie Mac ended the week at $13.50, up over 300% in 2025. Notably, both stocks commenced 2025 trading at approximately $3 per share. These dramatic gains are largely driven by growing investor confidence that the Donald Trump administration will finally release the mortgage agencies from federal conservatorship, a pivotal move that Bill Ackman has vocally supported for many years. Pershing Square is believed to be among the largest holders of these companies’ shares, with an estimated combined total of 180 million shares, including approximately 115 million of Fannie Mae. The total value of these holdings is now believed to be close to $2.5 billion.

Ackman’s investment philosophy is characterized by a highly concentrated portfolio, typically focusing on about half a dozen core investments. Over time, Bill Ackman has strategically shifted his focus away from short selling to exclusively target what he describes as “durable growth companies.” His current portfolio includes major enterprises such as Uber Technologies, Alphabet, Brookfield Asset Management, and Restaurant Brands International. Pershing Square, founded by Ackman in 2004, initially gained widespread recognition for his high-profile short position against bond insurer MBIA and his successful intervention in rescuing mall operator General Growth Properties during the financial crisis. Today, Pershing Square manages an impressive $20 billion in assets.

Beyond his investing acumen, Bill Ackman is also well-known for his outspoken public views. With more than 2 million followers on X (formerly Twitter), his influence extends significantly beyond the financial sector. In 2024, Ackman garnered considerable media attention for his public campaign advocating for the resignation of Harvard University president Claudine Gay, citing allegations of plagiarism and antisemitism, which ultimately led to her departure in January 2024. Furthermore, Ackman surprised many by endorsing Donald Trump for president in the 2024 election, signifying a notable departure from his decades-long history of supporting Democratic candidates.

Ackman's career is marked by bold and often contrarian investment decisions. A notable example is his highly successful move in 2020, where he famously earned $2.6 billion by shorting the bond market in anticipation of the COVID-19 pandemic crash. The profits from this shrewd move were subsequently reinvested to bolster long-term positions. Other historically successful investments that remain core holdings in Pershing Square’s portfolio include Canadian Pacific Railway and Chipotle Mexican Grill.