American Electric Power Company, Inc. (AEP) is a public utility holding company engaged in the generation, transmission and distribution of electric power to retail customers, and supplying and marketing of electric power at wholesale to other electric utility companies, municipalities and other market participants. The subsidiaries of the Company include Appalachian Power Company (APCo), Columbus Southern Power Company (CSPCo), Indiana Michigan Power Company (I&M) Ohio Power Company (OPCo), Public Service Company of Oklahoma (PSO) and Southwestern Electric Power Company (SWEPCo). The public utility subsidiaries of AEP are engaged in providing electric service, consisting of generation, transmission and distribution, on an integrated basis to their retail customers.