Southern Union Company. The Group's principal activity is to distribute and sell natural gas to residential, commercial and industrial customers located primarily in Texas, Missouri, Pennsylvania, Rhode Island and Massachusetts. The Group through its subsidiaries markets natural gas to end- users and operates natural gas pipeline systems, generate electricity, distribute propane and sell commercial gas air conditioning and other gas-fired engine-driven applications. Subsidiaries of Group have been established to support and expand natural gas sales and other energy sales and to capitalize on the Group's energy expertise.