Cox is a member of the board of directors of ophthalmic technology maker RxSight, Inc., and governance, risk and compliance firm ACA Compliance Group. He is a life trustee of the University of Southern California and a member of the advisory boards of private equity firm Starr Investment Holdings, RevOZ Capital, the United States Energy Security Council, and the Loker Hydrocarbon Research Institute, founded by Nobel Prize winner George A. Olah. He formerly served on the boards of health care companies Alphaeon Corporation and Calhoun Vision, Inc., photonics manufacturer Newport Corporation, and governance, risk and compliance firm Thomson Reuters Accelus. For ten years he was a member of the board of directors of the National Endowment for Democracy, and of the board of trustees of Chapman University.