The U.S. Department of Justice (DOJ) described the outcome of its investigation into Vistra Corp.’s acquisition of Cogentrix Energy, which Vistra agreed to acquire from Quantum Capital Group. The companies own electricity-generation assets and compete in wholesale electricity and capacity auctions. Their portfolios overlap in PJM Interconnection, ISO New England (ISO-NE), and the Electric Reliability Council of Texas.

During the Federal Energy Regulatory Commission’s (FERC) review, ISO-NE’s Internal Market Monitor warned that the transaction could reduce competition and allow Vistra to exercise market power. While the FERC application was pending, Vistra decided to sell its Casco Bay Energy facility in ISO-NE. FERC approved the transaction without conditions, taking that decision into consideration.

The DOJ continued its investigation after FERC’s approval to assess whether Vistra could still have the ability and incentive to withhold electricity from the ISO-NE market after the acquisition. The department reviewed thousands of documents, conducted economic modeling, and interviewed industry participants. It remained concerned that the combined generation portfolio could substantially lessen competition, even after the Casco Bay sale. Its analysis followed the framework used in its 2025 settlement concerning Constellation Energy’s acquisition of Calpine.

Vistra and Cogentrix then decided to sell Cogentrix’s gas-fired combined-cycle power plant in Rumford, Maine. The DOJ said the sale would reduce the combined company’s ability and incentive to withhold electricity and raise prices in ISO-NE. The department expects the divestitures to save consumers across New England tens of millions of dollars annually and said it will monitor the Rumford sale. Until then, the companies must comply with applicable FERC regulations. The DOJ emphasized that its conclusions are specific to the facts of this investigation.