One closely watched hedge fund manager is Bill Ackman, who has made a name for himself by making concentrated bets as the head of Pershing Square Capital Management. In early 2023, Ackman and Pershing Square first started buying stock in Alphabet (NASDAQ: GOOGL) (NASDAQ: GOOG).

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Over the last two quarters, Ackman has built two new significant positions for Pershing Square -- Nike (NYSE: NKE) and Brookfield (NYSE: BN) -- piling an estimated $2.2 billion into those stocks during the third quarter alone. Here's why.