Troubled Japanese supermarket chain Seiyu has said that its shareholders had approved the appointment of five executives from US retail giant Wal-Mart to Seiyu's board of 13 directors. This moves follows the news in December that Wal-Mart was to substantially increase its stake in the Japanese supermarket retailer to 37.7%. The US retailer has an option to further increase its stake in Seiyu to 66.7% by the end of 2007.