[3] He spent his first two undergraduate years at Southern Methodist University and received an M.B.A. from the Harvard Business School.
[3] Cox served on the board of directors of Halliburton and the American Petroleum Institute.
[4] He served on the board of trustees of Southern Methodist University from 1973 to 1987, including as its chairman from 1976 to 1987.
[3] Cox lived in a US $40 million mansion in Highland Park, Texas, a wealthy enclave of Dallas.
[5][6] The large collection of French impressionists (Gustave Caillebotte, Cézanne and Van Gogh)[7] compiled by Cox was auctioned off by the heirs at Christie's in 2021.