Bill Ackman Is Buying These 4 Stocks: I Ranked Their Moats

Bill Ackman's Pershing Square Capital Management operates with a distinctly concentrated portfolio approach, allocating over 62% of its $15 billion in assets under management to just four stocks as of mid-2026. This concentration strategy reflects Ackman's confidence in identifying secular growth opportunities with defensible competitive advantages. His largest position, Brookfield Corp., represents 18.2% of the portfolio, followed by Uber Technologies at 15.9%, Amazon at 14.3%, and Alphabet at 13.8%. Meta Platforms rounds out his top five holdings at 11.4% of invested assets.

The portfolio demonstrates a pronounced tilt toward technology and digital infrastructure sectors, with a particular emphasis on companies positioned to benefit from artificial intelligence deployment and sustainable market moats. Unlike traditional hedge fund managers who maintain broader diversification across 25 or more positions, Ackman has deliberately limited Pershing Square's total holdings to approximately 10 companies, placing significant conviction behind each thesis. This approach prioritizes deep fundamental analysis and portfolio weight allocation over the risk-mitigation benefits of traditional diversification.

Ackman's track record has validated this concentrated strategy during 2024 and into 2026, as his personal net worth more than doubled from $4.3 billion to an estimated $9.2 billion. The outperformance reflects both strong absolute returns from his core positions and the amplification effect of concentrated ownership during periods when large-cap technology and infrastructure companies command substantial market valuations. However, financial professionals caution that this approach carries elevated idiosyncratic and concentration risk, particularly for investors without Ackman's analytical resources, institutional access, and capital base to weather significant drawdowns in concentrated positions.

The billionaire's stock selection methodology emphasizes sustainable competitive advantages and long-term secular tailwinds rather than tactical market timing. His investments span infrastructure (Brookfield), mobility and logistics (Uber), cloud computing and digital commerce (Amazon), search and digital advertising (Alphabet), and social media (Meta), collectively representing exposure to fundamental technological and economic transformation themes. This thematic coherence across holdings suggests Ackman views these positions as complementary exposures to overlapping secular growth narratives rather than a diversified basket of uncorrelated bets.