The Foreign Intelligence Surveillance Court, in a document released yesterday, said the government should review which documents should be declassified and inform the court of its decision by July 29.
The case dates back at least to 2008, when the court issued an order, reportedly requiring Yahoo! to allow the government to obtain access to customer data. The Justice Department took "no position" on the request, according to the court document.
Yahoo! asked the court on June 14 to release documents about the program, shortly after revelations of the vast data collection program known as PRISM.
Other Internet companies including Google and Microsoft have also sought declassification of documents.
The companies have stated they release information only in response to specific court orders, and claim that reports about providing easy access to US authorities are exaggerated.
Apple, Facebook, Microsoft and other top Internet and technology companies have come under heightened scrutiny since word leaked of the vast, covert Internet surveillance program US authorities insist targets only foreign terror suspects and has helped thwart attacks.