petroleum

Although it is dwarfed by the likes of Exxon Mobil and Chevron, Hess Corporation (formerly Amerada Hess) is a sizeable integrated oil company with a half-share in a big refinery in the Virgin Islands, some 1,250 gas stations in the eastern United States, and exploration and production activities in the Gulf of Mexico, the North Sea, Africa, Russia, Azerbaijan, and Southeast Asia. Leon Hess built the company over the course of half a century and also owned the New York Jets professional football team.

Occidental Petroleum Corporation's principal activity is sell crude oil and natural gas. The company's operations are carried out through many subsidiaries and affiliates. Two major subsidiaries are Occidental Chemical Corporation and Occidental Oil and Gas Corporation. The company also owns 76% of OxyVinyls, the primary maker of PVC in North America.

Since its privatization in the 1990s, Spain’s Repsol YPF has become one of the world’s largest integrated oil companies. While retaining its dominant position in its home country, Repsol made a major push into South America, becoming the largest foreign energy player on that continent. The YPF part of its name reflects a major acquisition in Argentina.

Noble Energy is an independent oil and gas exploration and production company with operations in the western United States, the Gulf of Mexico, the Middle East, the North Sea and West Africa. Some of its most significant (and most controversial) activity is off the coast of Equatorial Guinea, whose dictator Teodoro Obiang has been accused of using little of the revenue from foreign energy companies to help his own people.

StatoilHydro is the leading integrated energy company of Norway and the largest off shore oil and gas corporation in the world. It has operations in nearly 40 countries worldwide and was the result of a recent merger between Statoil and the oil and gas division of Norsk Hydro. StatoilHydro has been cited on a number of cases regarding environmental issues and corruption.