Oil major BP (BP.L) agreed to pay a civil penalty of $10.75 million to cover allegations company traders manipulated natural gas markets in 2008, which is less than BP has already paid in the case, U.S. energy regulators said in a filing.

The U.S. Federal Energy Regulatory Commission (FERC) alleged that BP violated the Natural Gas Act by manipulating the next-day gas market at Houston Ship Channel from mid-September through Nov. 30, 2008.

BP paid a civil penalty of $24,356,686 in December 2020 and disgorgement of unjust profits of $250,295 in January 2021 in the case. But the company paid those penalties under protest and appealed the case to the U.S. Court of Appeals for the Fifth Circuit, which remanded the matter back to FERC to reassess the civil penalty.

The settlement announced in the filing late on Friday resolves the case.

FERC said under the settlement BP will not seek return of the $250,295 of disgorgement it has paid.

The regulator also said its Office of Enforcement "will not object should BP choose to seek to reclaim the excess payment of $13,606,686 through a suit" in the U.S. Court of Federal Claims or any other forum of competent jurisdiction.

Officials at BP were not immediately available for comment.

The case related to actions by BP traders to take advantage of market dislocations around the time Hurricane Ike smashed into the Houston area in September 2008.

FERC's Office of Enforcement alleged BP traders made uneconomic physical gas sales to suppress the Houston Ship Channel Gas Daily index and boost the value of BP's financial position.