Australia approved a request by Aluminum Corp. of China Ltd. (Chinalco) to increase its stake in mining giant Rio Tinto. Australian regulators said Chinalco will need government approval if it wants to raise its stake above 14.99 percent. That restriction means that Chinalco won’t get a seat on Rio’s board, and will have a hard time blocking BHP Billiton’s pending $143 billion offer for Rio. (MarketWatch)