Petroleo Brasileiro SA
Petrobras was founded in October 1953, inheriting Brazil's national oil assets from the National Oil Council and a variety of private firms. The nationalized company consolidated and then began to build up and diversify. The company's exploration led to major oil finds in the 1970s during which time the company became the world leader in deep sea oil drilling techniques. Today offshore production accounts for nearly three-quarters of the company's production. The company invested an estimated $85bn in its first 40 years but the pressure for privatization grew and in 1997 the government opened up the Brazilian market for the first time. This led to Petrobras beginning an aggressive expansion drive in the international markets, initially in South America with such projects as the Bolivia-Brazil gas pipeline but more recently with investments across the world.