Billionaire Bill Ackman, who follows an investment philosophy similar to Warren Buffett, has exposure in his Pershing Square Capital Management hedge fund to the artificial intelligence (AI) boom. That might go against his firm's usual focus of buying retail-based businesses.

Bill Ackman's Pershing Square has a portfolio valued at $11.930 billion, which is concentrated in these four stocks as of the end of Q1.

Pershing Square founder Bill Ackman made his professional tennis debut. In a doubles match at the Tennis Hall of Fame Open, he and his partner lost in straight sets in a match that lasted just 67 minutes.