Incorporated as Indian Oil Company Ltd. on 30th June 1959, it was renamed as Indian Oil Corporation Ltd. on 1st September 1964 following the merger of Indian Refineries Ltd. (established 1958) with it. Indian Oil and its subsidiaries account for approximately 48% petroleum products market share, 34% national refining capacity, and 71% downstream sector pipelines capacity in India.

The Indian Oil Group of companies owns and operates 10 of India’s 20 refineries with a combined refining capacity of 60.2 million metric tonnes per annum (MMTPA, .i.e. 1.2 million barrels per day). These include two refineries of subsidiary Chennai Petroleum Corporation Ltd.

The Corporation’s cross-country network of crude oil and product pipelines, spanning over 10,000 km and the largest in the country, meets the vital energy needs of the consumers in an efficient, economical, and environment-friendly manner.

Indian Oil is investing Rs. 43,400 crores (the US $10.8 billion) during the period 2007-12 in augmentation of refining and pipeline capacities, expansion of marketing infrastructure and product quality up-gradation as well as in integration and diversification projects.

Indian Oil Corporation Ltd. (IOCL) is the largest company being operated from India with Rs. 2,80,000 Crores as its annual turnover during the last year. It is the 116th globally ranked fortune 500 companies-highest from India. IOC’s core business is in the area of the energy sector and dominates the oil scenario in the country. Its Aviation Services Division supplies 65% of the Aviation Turbine Fuel (ATF) to air carriers in India at more than 95 fuelling locations country-wide.