Private equity group Providence Equity Partners has taken a 20 percent stake in Aditya Birla Telecom (ABTL) – a wholly-owned subsidiary of India’s Idea Cellular – for US$640 million. ABTL owns a mobile license for the Bihar service area and will hold a 16 percent stake in Indus Towers, the company’s tower subsidiary which is co-owned by Vodafone Essar and Bharti Airtel.