NiSource Inc. is an energy holding company whose subsidiaries provide natural gas, electricity and other products and services to approximately 3.8 million customers located within a corridor that runs from the Gulf Coast through the Midwest to New England. The Company is a natural gas distribution company operating east of the Rocky Mountains. Its business segments include Gas Distribution Operations; Gas Transmission and Storage Operations; Electric Operations, and Other Operations. NiSource's principal subsidiaries include Columbia Energy Group, a vertically integrated natural gas distribution, transmission and storage holding company whose subsidiaries provide service to customers in the Midwest, the Mid-Atlantic and the Northeast; Northern Indiana Public Service Company, a vertically integrated gas and electric company providing service to customers in northern Indiana, and Bay State Gas Company, a natural gas distribution company serving customers in New England.