The ratings on Exelon Generation Co. LLC reflect the nonregulated operating company's relationship with parent Exelon Corp., which as a consolidated entity has a slightly below-average business profile and a moderate financial profile. The ratings on Exelon and its subsidiaries are on CreditWatch with negative implications in response to the announced merger between Exelon and Public Service Enterprise Group Inc. (Enterprise). If completed, the merger will create the largest utility holding company in the U.S. Chicago, Ill.-based Exelon has about $10 billion in debt outstanding, net of stranded-cost securitization bonds. Similarly, Newark, N.J.-based Enterprise has about $10 billion in outstanding debt, net of stranded-cost securitization bonds. Standard&Poor's expects to resolve the CreditWatch listings on or near the completion