When a company expands its business across a whole chain within the same industry and controls both the upstream supplies and downstream buyers, which happens a lot in the oil industry. In the oil and gas industry this would imply being active all the way along the supply chain from locating crude oil or gas deposits, drilling and extracting the hydrocarbons, transporting it either in pipelines or tankers, refining it into petroleum products, distributing the fuel locally and marketing it to consumers. A vertically integrated gas company is one in which natural gas and transportation are sold as a bundle to final consumers