Warren Buffet's Berkshire Hathaway could soon become Bank of America's biggest shareholder, if the company gets an OK from US regulators today, write Rachel Louise Ensign and Nicole Friedman for The Wall Street Journal. 

Berkshire Hathaway has said it will swap its large holding of preferred stock in Bank of America for common stock if the bank raises its dividend. A favourable stress-test verdict from the US Federal Reserve today - in the second round of its annual health check of the industry - may allow the bank to do just that.