Billionaire Bill Ackman, who runs Pershing Square Capital Management, is heavily exposed to the artificial intelligence (AI) build-out trend through three major stock picks: Amazon, Microsoft, and Meta Platforms. Microsoft, a value-oriented investment for Ackman, makes up 15% of Pershing's portfolio. Microsoft's Q4 of fiscal year (FY) 2026 was highlighted by 43% Azure revenue growth, with overall revenue rising 18% year over year and earnings per share rising 23%, causing the stock to pop 15.5% the day following earnings. The stock is still fairly cheap at 23 times forward earnings. Amazon also delivered big results, with its stock taking a big jump following earnings. Amazon Web Services (AWS) grew at a 37% pace, blowing past the 31% growth Wall Street analysts were expecting. Ackman first initiated his Amazon position during Q2 last year. Meta Platforms still has some work to do before it can turn around its fortunes.