India's Satya Nadella, Microsoft's cloud-and-enterprise chief and, Tony Bates, former Skype CEO, are among the internal candidates shortlisted to replace the outgoing Microsoft CEO Steve Ballmer, sources said. Microsoft, which started with about 40-names, has also shortlisted 5 external candidates including Ford Motor's Alan Mulally and former Nokia CEO Stephen Elop. In August Ballmer said he would retire within 12-months.