A secret legal battle between the U.S. government and Yahoo Inc. YHOO +3.93% over requests for customer data became so acrimonious in 2008 that the government wanted to charge the Internet company $250,000 a day if it didn't comply.
Yahoo made the threat public Thursday after a special federal court unsealed 1,500 pages of legal documents from a once-classified court battle over the scope of National Security Agency surveillance programs. The documents shed new light on tensions between American technology companies and the intelligence community long before former NSA contractor Edward Snowden began leaking in 2013.

Source - http://online.wsj.com