Berkshire Hathaway, the big American investment company that acquired a 20 percent stake in Masai Barefoot Technology (MBT) in 2007, is said to be preparing to increase it to a controlling interest. Company officials would not comment, but they denied a rumor that Jan Stig Andersen, the former Danish Ecco executive, is about to quit the post of chief executive at MBT. While stressing that MBT operates in the higher-end casual/physiological footwear market, they acknowledge that the recent turbulence in the toning category has affected MBT's results, particularly in the second half of 2010. Sales dropped by double digits in the U.S. Germany and the U.K. also experienced significant declines. However, MBT's sales and orders have been rising significantly in markets such as Italy, Spain, the Benelux region, Turkey and several parts of Asia. The company has just signed a deal for the Chinese market with 3A Shoes, based in Zhonghan, Guandong province.