• TATA Power Company Ltd.
• Pragati Power Co. Ltd.
• Oil & Natural Gas Corporation Ltd.
• Oil India Limited
• Cairn India Ltd.
• Hindustan Oil Exploration Company Ltd
• SAFWAN Petroleum Technologies Company, Kuwait
• Sedco Forex International Drilling Inc.
• Hitech Drilling Services India Ltd
• Dowell Schlumberger
• Anadril Schlumberger
• Vector Schlumberger
• IL&FS Energy Development Company Ltd.
• Punjab Biomass Power Limited