Shares of Constellation Energy Corporation plunged on Friday, slipping as much as 9.8% to $307.71 in after-hours trading after fluctuating between $350.62 and $300.45 earlier. The selloff came after the White House urged PJM Interconnection—the country’s largest electric grid serving 67 million customers across 13 states plus Washington, D.C.—to hold a one-time emergency procurement auction for new power plants and impose limits on earnings for existing plants in PJM’s capacity market, which pays generators to stay on standby. This follows a recent PJM capacity auction that saw prices surge over 800% compared to last year. Pennsylvania Governor Josh Shapiro criticized PJM for being “too damn slow” amid rising power bills.