Valero Energy Corp/tx
One of the world's largest independent petroleum refiners, this Texas company turns crude oil into gasoline, diesel, jet fuel, and asphalt at refineries in the United States, Canada, and the United Kingdom, and also makes ethanol and renewable diesel. It was born in 1980 as the biggest corporate spinoff in U.S. history, when a Houston gas company's pipeline arm was split off and moved to San Antonio. Its name comes from Mission San Antonio de Valero — the original name of the Alamo.