Exelon Corporation is a utility services holding company. The Company, through its subsidiary, Exelon Generation Company, LLC (Generation), is engaged in the generation, delivery, and marketing of energy business. The Company, through its subsidiaries, Commonwealth Edison Company (ComEd), PECO Energy Company (PECO), Baltimore Gas and Electric Company (BGE), Pepco Holdings LLC (PHI), Potomac Electric Power Company (Pepco), Delmarva Power & Light Company (DPL) and Atlantic City Electric Company (ACE), is engaged in the energy distribution and transmission business. It operates through 11 segments: Generation's five segments: Mid-Atlantic, Midwest, New York, ERCOT, Other Power Regions, ComEd, PECO and BGE, and PHI's three utility segments: Pepco, DPL and ACE. Generation's integrated business consists of the generation, physical delivery and marketing of power across geographical regions through its customer-facing business.