The U.S. Securities and Exchange Commission (SEC) has charged Canadian energy firm Penn West Petroleum Ltd. and three of its former top executives with accounting fraud.

The SEC alleges that Penn West, which has since been renamed Obsidian Energy Ltd., “fraudulently moved hundreds of millions of dollars in expenses from operating expense accounts to capital expenditure accounts.”

The alleged fraud allowed the firm to artificially reduce its operating costs, improving its extraction efficiency metrics and profitability, the SEC says. The SEC also alleges that the fraud was orchestrated by three of the company’s former top finance officials. The allegations have not been proven.

The SEC’s complaint, which was filed in federal court in Manhattan, charges Penn West and the three former executives with violating the anti-fraud, reporting, books and records and internal controls provisions of the federal securities laws. The regulator is seeking permanent injunctions and monetary relief against all the defendants, officer-and-director bans and a clawback of incentive-based compensation awarded to its former chief financial officer.

One of the former executives is co-operating with the SEC’s litigation and has agreed to a settlement that includes permanent injunctions and an officer-and-director ban without admitting or denying the SEC’s findings. The settlement is subject to court approval.

The SEC also says that its investigation found no misconduct by the firm’s former CEOs, Murray Nunns and David Roberts, who have reimbursed the company for bonuses and certain stock awards that they received when the company allegedly committed accounting violations. In 2014, the company restated its financial statements from 2012 to the first quarter of 2014.

“Combating financial fraud is critical to maintaining a fair and transparent marketplace,” says Stephanie Avakian, co-director of the SEC’s enforcement division, in a statement. “We will continue to vigorously pursue and punish corporate executives and other individuals whose actions violate the federal securities laws.”