Howard Hughes Holdings Inc.’s stock rose Monday as billionaire Bill Ackman reached a final agreement to acquire a controlling interest in the real-estate-development company that he plans to turn into a modern Berkshire Hathaway.

Ackman is assuming effective control of Howard Hughes, a listed real estate development company he already partially owns, with a further $900mn investment in the Texas-based group. Under the agreement,

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.

Billionaire hedge fund manager Bill Ackman spoke about the benefits an investment firm can realize from acquiring or building an insurance company and what it means for Howard Hughes Inc., in a CNBC interview on Monday.

Bayliss, Shivansh Tiwary (Reuters) -Billionaire investor Bill Ackman said on Monday that he raised his stake in real estate company Howard Hughes, realizing a long-held dream of creating a diversified holding company modeled after legendary investor Warren Buffett's Berkshire Hathaway.