Billionaire Bill Ackman has built a $35 billion hedge fund, led high-profile overhauls at companies like Chipotle, and boasts an eye-watering investment portfolio through his firm, ranging from Amazon to Microsoft. Now he’s revealing the two things that moved the needle in his career: a book that inspired Warren Buffett and a $14,000 side hustle.
“One early formative experience was at Harvard, where I took a job at Harvard Student Agencies selling advertising for the Let’s Go travel guides—a series of books where Harvard students wrote reviews of hotels around the world,” Ackman recently told editor-in-chief Alyson Shontell during Fortune podcast Titans and Disruptors of Industry.
“It was a commission-based business, and I turned out to be a good salesman,” he continued. In fact, he was so good at the job that the student agency was afraid he would outearn his superiors. “I made $14,000, which felt like a huge amount of money.”
As a teenager, Ackman told his dad that he’d be a millionaire by 30, have $100 million by 40, and be a billionaire by 50. And that commission check was his first taste of business success.
Then, after graduating, he returned home to work for his father, who cofounded and ran New York–based commercial real estate firm Ackman-Ziff Real Estate Group. Ackman wasn’t too thrilled about the job, but it pointed him toward the career he wanted to build. “I found the entrepreneurs and developers on the other side of the phone more interesting, and I decided I wanted to be an investor,” he said. And his father—an entrepreneurial success in his own right—led him further down the investing rabbit hole. “My dad introduced me to a man named Leonard Marks, who recommended The Intelligent Investor by Ben Graham.” Graham is known as the “Father of Value Investing” and profoundly influenced the young Warren Buffett’s investing style, which Ackman came to greatly admire.
Ackman completed his MBA at Harvard Business School in 1992, and that same year cofounded his first investment firm, Gotham Partners, with fellow Harvard graduate David Berkowitz.
“I went to business school to learn how to be an investor and just followed that path—fortunate to find something I was excited about,” Ackman added.
Now, Bill Ackman’s Pershing Square Capital Management is a $35 billion titan
In 2004, after winding down his Gotham Partners venture, Ackman founded New York–based investment firm Pershing Square Capital Management.
Over more than two decades under his leadership as CEO, the company has grown to become a $35 billion titan of industry.
Its long-term returns have crushed the market. Those who stayed in since inception have seen their investments compound nearly 16.5% annually for two decades, compared to a 10% return on the S&P 500 over the same period. However, in 2026, the company has recently been underperforming, with Pershing Square Holdings down 11% year to date this February compared to the S&P 500’s roughly 1% gain. Still, in April, Pershing Square raised $5 billion in the largest closed-end fund listing in U.S. history through its combined IPO.
The 60-year-old hedge fund mogul has also grown his own net worth to $11.5 billion, and his influence has grown commensurately.
A well-timed 2020 bet on corporate credit markets during the COVID-19 crash reportedly turned $27 million into $2.6 billion in a matter of weeks. His 2016 bet on Chipotle also paid off handsomely, with Pershing Square nearly doubling its original $1.2 billion investment within a few years, and later selling off its stake. And around a decade ago, his activist campaign at Canadian Pacific Railway became one of the most celebrated turnarounds in modern investing.
Ackman is a ‘Warren Buffett devotee’ looking to emulate his success
Ackman is still a self-proclaimed “Warren Buffett devotee” who has looked up to the legendary investor as an “unofficial mentor.”
In March, he sought to replicate Buffett’s success with Berkshire Hathaway by taking Pershing Square Capital Management public and gaining access to “permanent capital.” To entice investors, every 100 shares of the closed-end fund they buy will automatically earn them 20 free shares of Pershing Square.
Ackman explained that about 98% of Pershing Square’s capital is invested in public companies, where it is often one of the largest shareholders. Because investors can sell their shares to other investors rather than redeeming directly from the funds, the vehicles can generally retain their capital and investments. This is similar to Berkshire Hathaway’s permanent-capital structure.
“That gives us what Mr. Buffett would call permanent capital,” Ackman explained during the podcast. “Berkshire is a corporation. When people want their money out, they sell Berkshire shares, but the capital stays in the enterprise, and Buffett has done a remarkable job investing it over time.”
