Unit

Founded in 1963, Unit Corp. engages in onshore contract drilling of oil and gas wells (for its own account as well as for other companies), exploration and production of oil and gas, and the gathering and transportation of natural gas primarily in the U.S. It also explores, develops, acquires and produces oil and natural gas, and purchases, sells, gathers, processes and treats natural gas. It operates in Oklahoma, Texas, Louisiana, and Kansas. The company itself is based in Tulsa, OK.