A unanimous three-judge panel of the 9th U.S. Circuit Court of Appeals said that a lower court judge wrongly tossed out the lawsuit after the government asserted the case was a "state secret" that would harm national security if allowed to go forward.

The trial court judge dismissed the case before the prisoners could present evidence allegedly showing that the company's participation in the program was illegal. The Bush administration and then the Obama administration argued that the lawsuit should be thrown out before the government turns over any evidence because the nature of the legal action is itself a classified matter.

The federal government inserted itself into the lawsuit on the company's side because it said feared top-secret information would be disclosed.

The appeals court, however, said the five prisoners suing San Jose-based Jeppesen Dataplan Inc. can try to prove their case without using top-secret information that legitimately needs protection from disclosure.