Devon Energy Corporation is a Delaware corporation formed in 1971 and incorporated on May 18, 1999. It is an independent energy company engaged in the exploration, development and production of oil, natural gas and NGLs. The Company's operations are concentrated in various North American onshore areas in the U.S. and Canada. It also own natural gas pipelines, plants and treatment facilities in many of its producing areas, making it one of North America's processors of natural gas. Its marketing and midstream revenues are mainly generated by: selling NGLs that are either extracted from the gas streams processed by its plants or purchased from third parties for marketing, and selling or gathering gas that moves through its transport pipelines and unrelated third-party pipelines. The Company's marketing and midstream costs and expenses are mainly incurred from: purchasing the gas streams entering its transport pipelines and plants; purchasing fuel needed to operate its plants, compressors and related pipeline facilities; purchasing third-party NGLs; operating its plants, gathering systems and related facilities; and transporting products on unrelated third-party pipelines. The Company's oil and gas operations are subject to various federal, state, provincial, tribal and local laws and regulations. Its operations also are subject to conservation regulations, including the regulation of the size of drilling and spacing units or proration units; the number of wells that may be drilled in a unit; the rate of production allowable from oil and gas wells; and the unitization or pooling of oil and gas properties.