ONEOK, Inc. (pronounced like 'one oak') (NYSE: OKE) is a diversified Fortune 200 corporation based in Tulsa, Oklahoma. Founded in 1906 as Oklahoma Natural Gas Company, it is one of the largest natural gas distributors in the United States.
Tulsa-based Fortune 500 Corporations (by size):ONEOK • Williams Companies
Tulsa-based Fortune 1000 Corporations (by size):Companies listed above, plus: Dollar-Thrifty Automotive Group
Major Tulsa-based private corporations (Fortune's Largest Private Companies):SemGroup (5) • QuikTrip (28) • Vanguard Automotive Group (103) • Red Man Pipe and Supply (307)