Constellation Energy Corporation is an American energy company headquartered in Baltimore, Maryland. The company provides electric power, natural gas, and energy management services. It has approximately two million customers across the continental United States.

Exelon Corporation is a public utility headquartered in Chicago, and incorporated in Pennsylvania. Exelon is the largest electric parent company in the United States by revenue and is the largest regulated electric utility in the United States with approximately 10 million customers. The company is ranked 99th on the Fortune 500.