Reading Time: 2 minutesKey Takeaways:

Microsoft is now a major part of Pershing Square’s portfolio and the new $PSUS fund.
Ackman started buying shares in February 2026 after the stock price fell.
The stock was purchased at 21x forward earnings, which Ackman called a highly compelling price.
The investment is based on Microsoft’s leading role in the AI revolution and its integration of Copilot.

Billionaire investor Bill Ackman has confirmed that Microsoft is now a core holding in Pershing Square’s portfolio, taking advantage of price drop to secure a highly compelling valuation driven by the company’s AI leadership.

As two of the largest forces in equity markets — growing index ownership and increasing amounts of capital controlled by extremely short-term-oriented, leveraged, volatility-intolerant investors — converge, we have found occasional opportunities to acquire some of the most…
— Bill Ackman (@BillAckman) May 15, 2026

Strategic Accumulation During a Market Gap
Billionaire investor Bill Ackman officially added Microsoft to the core holdings of Pershing Square Capital Management. According to a 13F filing, Ackman began accumulating shares in February 2026. This move followed a sharp drop in Microsoft’s stock price after the company released Fiscal Q2 results. During the same period, the Nasdaq index rose, then creating a massive performance gap. Ackman viewed this disconnect as a rare opportunity to buy the dip on one of the world’s most dominant technology companies.
Microsoft is now a major part of Pershing Square’s portfolio
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AI Leadership and Compelling Valuation
The core of Ackman’s investment thesis is based on Microsoft’s leadership in the artificial intelligence sector and its currently attractive valuation. He noted that the company is trading at approximately 21x forward earnings, which is in line with the broader market average but far below Microsoft’s own average valuation from recent years. Ackman described this as a highly compelling entry point for a business that stands at the forefront of AI integration. This follows a similar move in February when he added Meta Platforms to his portfolio, signaling a strong shift toward large cap tech giants that are poised to benefit most from the AI revolution.
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A Central Pillar for Pershing Square USA
This position is a part of the Pershing Square USA fund, a closed end fund that debuted on the New York Stock Exchange in April 2026. By making Microsoft a core holding, Ackman is pivoting his strategy to include more high growth technology names while maintaining his signature long term conviction approach. Despite a challenging performance for Pershing Square at the end of 2024, Ackman is betting that the combination of AI driven growth and a disciplined entry price will lead to a strong recovery for his investors throughout 2026.
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