The United States owes $1.1 billion to 11 oil and gas companies for breaching their leases to explore off the coast of California, the U.S. Court of Appeals for the Federal Circuit said Monday in an opinion upholding the lower court.

The 2006 damage award handed down by the U.S. Court of Federal Claims is believed to be one of the largest in that court’s 150-year history. The oil and gas companies, represented by Covington & Burling, sued for breach of contract after the federal government blocked them from drilling off California.