Berkshire Hathaway Inc.'s board of directors should update shareholders annually on the status of Chief Executive Officer Warren Buffett's successor, to ensure the firm sticks to a plan to name an insider, the AFL-CIO said. Berkshire opposes the union's proposal that the firm have a written policy to ease the eventual transition from Buffett, 81, who said last month that the Omaha, Nebraska-based company had identified a successor, without publicly disclosing who that is. "We're pleased they have picked an internal candidate because that's important for the success of a company with a strong culture like Berkshire Hathaway," said Brandon Rees, acting director of the AFL-CIO office of investment. "We'd prefer to have an assurance it's the board driving the process and have an annual update on the process." Apple Inc., News Corp., FedEx Corp. and Bank of America Corp. are among firms whose investors previously had raised concerns that succession planning lacked clarity.