The STX Group has paid $800 million for a 39.2 percent interest in Aker Yards, making the Korean company the single largest shareholder in the Norwegian-based shipbuilding company. The purchase is seen as a move for the Koreans to move into the cruise-ship building sector as competition for other types of ships heats up with Chinese builders. STX is the fifth largest South Korean shipbuilder. Aker Yards has nine cruise ships under construction at its facilities in Finland and France.