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.

Exelon Generation—owner and operator of the nation’s largest power reactor fleet—held an online event yesterday outlining the company’s business strategy as it prepares to separate from Exelon Corporation under the name Constellation. The separation is expected to become final on February 1.