Bill Ackman’s $15.5B Pershing Square Adds Meta and Doubles Amazon in AI Pivot

Pershing Square Capital Management, the concentrated activist fund run by Bill Ackman, disclosed a $15.5 billion equity portfolio in its February 13F filing, built around one rotation: a new $1.8 billion Meta stake and a doubled Amazon position, paid for with a full Chipotle exit.

On February 17, 2026, Pershing Square Capital Management filed its quarterly 13F-HR (the SEC form U.S. institutional managers use to disclose their stock holdings 45 days after each quarter end) reporting $15.53 billion in equity positions across 10 issuers as of December 31, 2025. The fund, founded by Bill Ackman in 2003 and famous for activist campaigns at Wendy’s, Target, and Howard Hughes, is one of the most concentrated marquee books on Wall Street. Q4 2025 quietly rebuilt half of that book around AI mega-cap technology.

That rebuild has two steps. First, Ackman closed an $844 million stake in Chipotle that Pershing Square had carried for years and let Restaurant Brands and Hilton drift on the position list. Second, he opened a fresh $1.76 billion Meta position in November and December and added 3.8 million shares of Amazon, lifting that stake by about 65 percent. The book is still concentrated. The thesis is no longer activist food and travel.

From $14.6B to $15.5B in One Quarter

Pershing Square ended September with $14.6 billion in disclosed equity positions across 10 issuers. Three months later the book sits at $15.5 billion across the same number of issuers, with one swap, Chipotle out and Meta in. The 6 percent step-up did not come from price action in the legacy holdings. It came from new buying. Ackman moved $1.8 billion of capital into Meta during the back half of Q4, expanded the Amazon position by 3.8 million shares, and let proceeds from the Chipotle exit fund part of those trades. Pershing Square sits in the same AUM band as Brad Gerstner’s Altimeter Capital and somewhat below Stanley Druckenmiller’s Duquesne Family Office, with a much smaller name count than either.

The Top 5 Positions and the Thesis Behind Them

Five names account for about 73 percent of the portfolio. Brookfield Corp is the largest at $2.82 billion. Brookfield is a Toronto-based asset manager that owns insurance, infrastructure, renewable power, and a growing book of data-center real estate leased to hyperscalers (Amazon, Microsoft, Google, Oracle, Meta and the largest AI labs). Uber is second at $2.47 billion, a position Pershing Square has framed as a long-cycle bet on autonomous-vehicle adoption. Amazon is third at $2.22 billion. Ackman lifted the position by 65 percent in Q4 as Amazon Web Services, the cloud arm that hosts a large share of frontier-AI training, kept booking new multi-billion-dollar compute backlogs. Alphabet is fourth at $2.15 billion combining Class A and Class C shares, where Google Cloud is the in-house AI growth engine and YouTube is the advertising base. Meta is fifth at $1.76 billion, a brand-new position opened across November and December 2025. Pershing Square’s February shareholder letter described Meta as a clear beneficiary of AI integration in advertising at a discounted valuation. Restaurant Brands International and Howard Hughes Holdings round out the next tier at about $1.5 billion each, the survivors of the older activist book.

Why This 13F Is Trending Now

The filing went public in February. The conversation came back this week. On April 28, Ackman’s Pershing Square USA closed-end fund priced its initial public offering and listed on the New York Stock Exchange. The vehicle holds the same positions as the underlying hedge fund, exposing the Q4 13F to a much larger retail audience for the first time. The stock traded below its $50 issue price on day one and again on day two, drawing wide coverage from CNBC, Bloomberg, and Reuters. Each of those write-ups walked through the underlying holdings as the substance of what the IPO was selling. Meta is up about 14 percent year-to-date, Amazon roughly 8 percent, and Alphabet about 12 percent.

What to Watch

The May 15 deadline: The next 13F-HR, covering March 31, 2026, is due by mid-May. The number to watch is whether Ackman expanded the Meta position above its 11.4 percent weight or trimmed it after the year-to-date rally.

Concentration risk: Five names already make up about 73 percent of the disclosed equity book. A bad print at Meta, Amazon, or Alphabet would now move Pershing Square’s mark-to-market value far more than at any other point in the last decade.

The activist question: Ackman’s edge has been concentrated activism in restaurants, railroads, and real-estate carve-outs. None of the new AI mega-cap holdings invite that playbook. Whether Pershing Square stays a passive holder of Meta, Amazon, and Alphabet, or eventually files a Schedule 13D (the SEC form an investor files within 10 days of crossing 5 percent ownership with intent to influence), is the open question.