Occidental Petroleum Corporation

The Occidental Petroleum Corporation was founded in 1920 but remained small until 1956, when Dr Armand Hammer sank $100,000 into the company, which was only worth about $34,000 at the time. Two wells were drilled and both came in. Hammer bought more stock and eventually took control of the company.Occidental discovered an important natural gas field in California in 1959 and in 1966 won a concession from Libya's King Idris to drill for oil. It discovered the billion-barrel Libyan oil field and, in need of outlets, bought the European refining and marketing arms of Signal Oil. It also diversified into the chemical industry and into coal mining. Under pressure from the new Libyan government led by Colonel Qaddafi - who had ousted Idris in a coup d'etat - Occidental agreed to sell 51% of its Libyan production to the Libyan government. The money raised was then invested in exploration in Latin America and in the North Sea, where it discovered the lucrative Piper field. In the 1980s Occidental sold off some of its international operations and invested $4bn in an oil and gas exploration company called Cities Service. Hammer hired Ray Irani to develop the company's chemical business which he did with great success. When Hammer died in 1990 Irani became Occidental's chief executive. he reduced the company's debt considerably by selling off its coal businesses and the North Sea operations and in 1994 he bought Agip's oil and gas holdings in the Gulf of Mexico.