B.P. is challenging the terms of its settlement in the 2010 Gulf Oil Spill.
A federal appeals court began hearing arguments in the case on Monday.
B.P. wants the court to overturn a federal judge’s ruling, upholding a court-appointed claims administrator’s interpretation of the settlement.
The oil company claims the administrator has let thousands of businesses receive hundreds of millions of dollars in payments for inflated and non-existent losses.
Lawyers for the businesses contended B.P. underestimated how many claimants would qualify.