Big oil

Big Oil is a name used to describe the world's seven or eight largest publicly owned oil and gas companies, also known as supermajors. The supermajors are considered to be BP plc, Chevron Corporation, ExxonMobil Corporation, Royal Dutch Shell plc, Total SA and Eni SpA, with ConocoPhillips Company also sometimes described in the past as forming part of the group.

The term, analogous to others, such as Big Steel, that describe industries dominated by a few giant corporations, was popularized in print from the late 1960s. Today it is often used to refer specifically to the seven supermajors. The use of the term in the popular media often excludes the national producers and OPEC oil companies who have a much greater role in setting prices than the supermajors. Two state-owned Chinese oil companies, CNPC and Sinopec, had greater revenues in 2013 than any of the supermajors except Royal Dutch Shell.

In the maritime industry, six to seven large oil companies that decide a majority of the crude oil tanker chartering business are called "Oil Majors".

The history of the supermajors traces back to the "Seven Sisters", the seven oil companies which formed the "Consortium for Iran" cartel and dominated the global petroleum industry from the mid-1940s to the 1970s. The Seven Sisters were:

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