Warren Buffett on Monday said his company Berkshire Hathaway overpaid in the $49-billion merger that created Kraft Heinz. "I was wrong in a couple of ways about Kraft Heinz," he added. Berkshire, which holds a 26.7% stake in Kraft Heinz, teamed up with Brazilian firm 3G in 2015 to merge Kraft Foods with HJ Heinz.