DTE Energy
Electric utilty company supplying electricity for residential and commercial use
Xcel Energy Inc.
Electricity and Natural Gas Company serving several Midwestern and Western states. Revenues are $11 billion.
PPG Industries
Manufacturer of glass, fiberglass, paint & coating, and fine chemicals
Covington & Burling LLP
Business and corporate law firm with offices in the District of Columbia, New York, and San Francisco, as well as London and Brussels.