The central public sector undertaking is a Maharatna, with the Ministry of Petroleum and Natural Gas overseeing its operations.

The company's history spans the discovery of crude oil in India in the year 1889, this was second in the World in the far east of India at Digboi and Naharkatiya, Assam to its present status as a fully integrated upstream petroleum company presently operating in more than 9 locations overseas.

Early in 1950s, Assam Oil discovered the first new oilfield in post-independence India, under the leadership of the geologist W. B. Metre, at Naharkatiya.

As of 2014[update] the company produced 3.466 MMT of crude oil, 2625.81 million cubic metre at standard conditions of natural gas and 46,640 tonnes of LPG.

The search for newer avenues has seen OIL spreading out its operations in onshore / offshore Orissa and Andaman, Cauvery offshore, Tamil Nadu, Arabian Sea, deserts of Rajasthan, onshore Andhra Pradesh, riverbeds of Brahmaputra and logistically difficult hilly terrains of the Indian state Mizoram and Arunachal Pradesh.

The company has accumulated over a hundred years of experience in the field of oil and gas production, since the discovery of Digboi oilfield in 1889.

[citation needed] The company has over 100,000 square kilometres (39,000 sq mi) of licensed areas for oil and gas exploration.

It has emerged as a consistently profitable International company[citation needed] and present in Libya, Gabon, Nigeria, Sudan, Venezuela, Mozambique, Yemen, Iran, Bangladesh and United States.

[citation needed] Presently, exploration activities are in progress along the Trust Belt areas of Arunachal, Assam including Mizoram.

[5] This joint venture gave birth to the exploration and drilling at two new sites in Naharkatiya and Moran in Dibrugarh district[6][7] which had then been just recently discovered.

[5] In 1981, the Government of India acquired 100% of the equity interest in the company which by then controlled all the oilfields of Tinsukia and Dibrugarh districts.

The company also sells its gas to different customers in Assam: Brahmaputra Valley Fertilizer Corporation Limited (BVFCL), ASEB, NEEPCO, Indian Oil Corporation's retail Assam Oil Division, and APL as well as to the Rajasthan Rajya Vidyut Utpadan Nigam formerly part of the Rajasthan State Electricity Board.

OIL's overseas E & P portfolio consists of 17 Blocks spread over 10 countries: Libya, Gabon, Nigeria, Yemen, Venezuela, USA, Mozambique, Myanmar, Bangladesh and Russia.

In addition to the above, OIL has 10% PI in 741 km long Multiproduct pipeline construction and operation project in Sudan which was completed in 2005.

(i) Legal and Contractual framework, (ii) Resettlement of the local community, (iii) Marketing of LNG, (iv) Project Financing, that must be sufficiently progressed before Operator Anadarko and the participants can determine economic viability and take Final Investment decision.