Coventry Health Care Inc.
A health insurer offering medical, Medicare, and Medicaid plans for Americans, Coventry Health Care was bought by Aetna in 2013. It began in 1986 in Nashville as the Coventry Corporation, co-founded by Phil Bredesen, who later became Tennessee's governor. The company took its final name after merging with Principal Health Care in 1998 and moving its headquarters to Bethesda, Maryland.