AEE

Ameren Corp

A utility holding company that delivers electricity and natural gas to homes and businesses across Missouri and Illinois through its Ameren Missouri and Ameren Illinois operations. It was created in 1997 when St. Louis–based Union Electric merged with CIPSCO, the parent of Illinois's Central Illinois Public Service — two companies with roots stretching back to the early 1900s. Its catchy name is a mash-up of "America" and "energy."