Paulson & Co. Founder John Paulson

Paulson & Co. Founder John Paulson

Rick Maiman/Bloomberg

John Paulson, best known for making $15 billion in 2007 betting against subprime mortgages, is rebounding with prescient bets on companies in takeovers, a strategy known as merger-arbitrage where got his start as a trader, and by investing in stocks that surged as global central bank policies propped up markets.