Exelon Corp. is a utility services holding company, which engages in the energy distribution and transmission businesses. The company is headquartered in Chicago, Illinois and currently employs 20,000 full-time employees. The firm is engaged in the energy distribution and transmission businesses through Commonwealth Edison Company (ComEd), Commonwealth Edison Company (PECO), Baltimore Gas and Electric Company (BGE), Potomac Electric Power Company (Pepco), Delmarva Power & Light Company (DPL), and Atlantic City Electric Company (ACE). The firm operates through six segments: ComEd, PECO, BGE, Pepco, DPL, and ACE. ComEd is engaged in purchasing and regulating retail sales of electricity. PECO is engaged in purchasing and regulating the retail sale of electricity and natural gas. Through its business services subsidiary, Exelon Business Services Company, LLC (BSC), the Company provides its subsidiaries with a variety of support services at cost, including legal, human resources, financial, information technology, and supply management services.