The deal involves Pershing Square buying 9 million newly issued shares of Howard Hughes for a total cost of $900 million. The purchase price is 48% above where the stock closed Friday, and puts Pershing's stake in the company at 46.

Howard Hughes Holdings said Bill Ackman’s Pershing Square Capital Management will invest $900 million in the company, boosting its stake further and bringing Ackman back into the fold.

(Reuters) - Billionaire investor Bill Ackman's Pershing Square Capital Management will buy 9 million newly issued shares of real estate developer Howard Hughes Holdings for $900 million, the companies said on Monday. The agreement will increase Pershing's stake in Howard Hughes to 46.9% from 37.6% it currently owns, the companies said.