Chevron, once part of the Standard Oil empire, has grown over the past quarter century into the world’s fourth largest petroleum company, thanks to a series of ambitious acquisitions: Gulf Oil in 1984, Texaco in 2001 and Unocal in 2005. The purchase of Texaco brought with it a massive environmental lawsuit that has dragged on for more than a decade. This is only one of a host of controversies surrounding Chevron’s environmental and human rights record around the world.