WASHINGTON (October 5, 2009)--The U.S. Supreme Court Monday let stand a court ruling that the Obama administration says will cost taxpayers at least $19 billion.

The ruling dealt with royalties on energy leases in the Gulf of Mexico.

The justices declined to hear the government's appeal of the ruling favoring Houston-based Anadarko Petroleum regarding eight deepwater leases Anadarko holds in the gulf.

The 5th U.S. Circuit Court of Appeals in New Orleans ruled the Interior Department couldn't collect royalties from the leases, even as oil prices rose and companies began posting huge profits.

The leases were obtained between 1996 and 2000 by Kerr-McGee Corp., which Anadarko later acquired.

The case revolves around a 1995 law that gave oil and natural gas producers a break from paying royalties at a time when energy prices were extremely low.

The law waived all royalty payments until a specific amount of oil and gas was produced.