Which of the following is not a Maharatana Company?

Various PSUs have been awarded additional financial autonomy. These companies are "public sector companies that have comparative advantages", giving them greater autonomy to compete in the global market so as to "support [them] in their drive to become global giants". Financial autonomy was initially awarded to nine PSUs as Navratna status in 1997. In 2010, the government established the higher Maharatna category, which raises a company's investment ceiling from Rs. 1,000 crores to Rs. 5,000 crores. The Maharatna firms can now decide on investments of up to 15 per cent of their net worth in a project while the Navaratna companies could invest up to Rs 1,000 crore without explicit government approval. Two categories of "Miniratnas" afford less extensive financial autonomy.  List of Maharatna 1.National Thermal Power Corporation (NTPC) 2.Oil and Natural Gas Corporation (ONGC) 3.Steel Authority of India Limited (SAIL) 4.Bharat Heavy Electricals Limited (BHEL) 5.Indian Oil Corporation Limited(IOCL) 6.Coal India Limited(CIL) 7.Gas Authority of India Limited(GAIL)