Bill Ackman Bets Big: 21% of $13.7 Billion Hedge Fund Anchored in Single Stock Play

Hedge fund titan Bill Ackman is making concentrated bets look fashionable again—staking nearly $3 billion on one company while traditional diversification strategies gather dust.

The Concentration Gambit

With 21% of his $13.7 billion portfolio riding on a single stock position, Ackman's move defies conventional Wall Street wisdom. The position represents one of the largest concentrated bets by a major hedge fund manager this decade.

High-Stakes Allocation

While most fund managers spread risk across dozens of positions, Ackman's heavyweight allocation suggests either supreme confidence or calculated recklessness—depending which finance PhD you ask.

Portfolio Mathematics

The $2.9 billion single-stock position dwarfs typical institutional allocations, where even 5% concentrations raise eyebrows among risk management committees.

Because nothing says 'alpha generation' like putting all your eggs in one basket and charging 2-and-20 for the privilege.

Image source: Getty Images.

Ackman is betting big on this growth tech stock

On an X post in February, Ackman said that his firm had accumulated 30.3 million shares in(UBER 0.35%). As of June 30, the hedge fund owned the same number of shares.

As mentioned, Ackman wants to identify great businesses. There are notable traits that help put Uber in this category.

Viewing Uber from a high level, investors realize that this is really a marketplace business that connects demand (riders and hungry consumers) with supply (drivers and restaurants). In general, these are fragmented stakeholder groups, which makes Uber tremendously valuable as the aggregator of supply and demand. The result is a powerful network effect, allowing the platform to get better over time.

The company's competitive position is so dominant that even popular restaurant chains with vast physical footprints and well-developed digital apps, likeand' Taco Bell, still make themselves available on its app. This is a strikingly clear indication of the power Uber has in the minds of consumers. The brand is held in high regard.

Uber is now a profit-making machine

Ackman praised the "superb job" that CEO Dara Khosrowshahi has done so far, turning Uber into a profitable company that produces free cash flow. This is a result of the CEO running a more efficient organization.

The bottom-line performance can also be credited to the scalable nature of the business model. Every additional ride or delivery should produce high margins for the company.

This is showing up in the financials. Operating income totaled $1.5 billion in the second quarter (ended June 30), up 82% year over year and a big improvement from the loss in the same period of 2022.

The leadership's confidence in the future was evident in Uber's 2024 investor day presentation. Management forecast adjusted EBITDA compound annual growth in a percentage range from the high 30s to 40, between 2024 and 2027. Based on Pershing Square's Uber investment thesis, the hedge fund believes those percentages are a realistic outlook.

Profit gains depend on revenue growth, and Uber's revenue was up 16% in the first six months of 2025 versus the same period in 2024. The growth has come down dramatically from 2021 and 2022.

However, double-digit annual revenue gains can be achieved for the foreseeable future. This will be possible because of Uber's ability to keep bringing on new customers, which now total 180 million monthly active users.

Is the stock still cheap?

Uber shares have had a wonderful 2025, climbing 57% (as of Oct. 14) thanks to strong fundamental performance. When Ackman and Pershing Square started buying the stock in January, they obviously thought it was cheap. The same perspective might still be true.

Even after a superb return, Uber shares look reasonably priced. Investors who want to follow in the billionaire's footsteps will have to pay a forward price-to-earnings ratio of 23.2. That's barely more expensive than theindex.

It can definitely be difficult to buy a stock after seeing the price rise so much and trade NEAR all-time highs. When it comes to investing, though, what matters is the future. Buying Uber shares today still looks like a smart move.