"Seven Sisters" was a common term for the seven multinational oil companies of the "Consortium for Iran" cartel, which dominated the global petroleum industry from the mid-1940s to the mid-1970s. Alluding to the seven mythological Pleiades sisters fathered by the titan Atlas, the business usage was popularized in the 1950s by businessman Enrico Mattei, then-head of the Italian state oil company Eni.
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The industry group consisted of:
Anglo-Iranian Oil Company (now BP)
Gulf Oil (later part of Chevron)
Royal Dutch Shell
Standard Oil Company of California (SoCal, now Chevron)
Standard Oil Company of New Jersey (Esso, later Exxon)
Standard Oil Company of New York (Socony, later Mobil, now part of ExxonMobil)
Texaco (later merged into Chevron)
Prior to the 1973 oil crisis, the Seven Sisters controlled around 85 percent of the world's petroleum reserves. Since then, industry dominance has shifted to the OPEC cartel and state-owned oil and gas companies in emerging-market economies, such as Saudi Aramco, Gazprom (Russia), China National Petroleum Corporation, National Iranian Oil Company, PDVSA (Venezuela), Petrobras (Brazil), and Petronas (Malaysia). In 2007, the Financial Times called these "the new Seven Sisters".