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).

Hey, you looking for a place on Manhattan's Upper West Side?Well, if you've got $20 million, Bill Ackman might be able to help you.Related: Billionaire Bill Ackman buys 3 million shares of battered consumer stockThe billionaire hedge fund manager has listed two neighboring apartments for a total of $19.

Pershing Square bought roughly 25.9 million shares of Brookfield in Q3, increasing its stake by almost 378%. Brookfield is a dividend stock, but I doubt there's an income investor on the planet who would get excited about the company's dividend.

Over the last two quarters, Ackman has built two new significant positions for Pershing Square -- Nike ( NKE 3.06%) and Brookfield ( BN 1.29%) -- piling an estimated $2.2 billion into those stocks during the third quarter alone. Here's why.