The April 2010 blowout of BP's Macondo well off the Louisiana coast triggered an explosion that killed 11 workers on the Deepwater Horizon drilling rig and led to millions of gallons of oil spilling into the Gulf. Shortly after the disaster, BP agreed to create a $20 billion compensation fund that was administered at first by the Gulf Coast Claims Facility, led by attorney Kenneth Feinberg.

BP argued that Barbier and court-appointed claims administrator Patrick Juneau misinterpreted terms of the settlement. Plaintiffs' lawyers countered that BP undervalued the settlement and underestimated how many claimants would qualify for payments.

In the panel's majority opinion, Judge Edith Brown Clement said BP has consistently argued that the settlement's complex formula for compensating businesses was intended to cover "real economic losses, not artificial losses that appear only from the timing of cash flows."

"The interests of individuals who may be reaping windfall recoveries because of an inappropriate interpretation of the Settlement Agreement and those who could never have recovered in individual suits for failure to show causation are not outweighed by the potential loss to a company and its public shareholders of hundreds of millions of dollars of unrecoverable awards," Clement wrote.

Judge Leslie Southwick wrote a concurring opinion. Judge James Dennis wrote a partial dissent, largely disagreeing with the other two.

"Because BP has not satisfied its heavy burden of showing that a change in circumstances or law warranted the modifications it sought, the district court correctly affirmed the Administrator's decision rejecting BP's argument and actions to modify the agreement," Dennis wrote.