Constellation, formerly Exelon Generation, owner and operator of the nation’s largest nuclear reactor fleet, announced this morning the completion of its separation from Exelon Corporation and its launch as a stand-alone, publicly traded company. Headquartered in Baltimore, Md., the new company began trading today on the Nasdaq Global Select Market under the symbol “CEG.”

Exelon announced last February that it had begun the effort to separate its utility businesses from its competitive power generation and customer-facing energy businesses.

The Nuclear Regulatory Commission has approved the indirect transfer of the licenses for 23 operating and five decommissioning reactors, as well as their associated independent spent fuel storage installations, from Exelon Corporation to a new company as part of a corporate restructuring, the agency announced yesterday.

Exelon Generation and Électricitéde France have asked the New York Public Service Commission to approve the transfer of EDF’s 49.99 percent ownership interest in Constellation Energy Nuclear Group (CENG) to Exelon, which owns 50.1 percent. CENG is the owner of New York’s Ginna and Nine Mile Point nuclear plants, as well as Maryland’s Calvert Cliffs.