Warren Buffett is stepping down as chairman of Berkshire Hathaway after serving in the role at the conglomerate for more than 50 years. Buffett, 96, will become chairman emeritus and will take on his new role immediately, the company said on Friday. His son, Howard, will become Berkshire Hathaway’s new chairman, part of a long-planned succession. Howard Buffett has been on the Berkshire Hathaway board since 1993. Warren Buffett will remain a director. He has served as Berkshire Hathaway’s...