10 Maharatna COMPANIES and 16 Navratna companies.There are also 60 Miniratna-1 category and 14 Miniratna-2 category companies.The 10 Maharatna companies are as follows:-1Bharat Heavy Electricals Limited(BHEL)2Coal India Limited(CIL)3Gas Authority of India(GAIL)4Indian Oil Corporation Limited(IOCL)5National THERMAL POWER Corporation Limited(NTPC)6Oil and Natural Gas Corporation Limited(ONGC)7Steel Authority of India Limited(SAIL)8Hindustan Petroleum(HPCL)9Power Grid Corporation of India Limited10Bharat Petroleum Corporation Limited(BPCL