The ACLU is scheduled to argue its NSA suit before a federal court judge in New York on Nov. 1.
In general, critics of the FISC opinion said the government could use the court's rationale to collect any information on Americans, from financial transactions to all Internet activity.
"The way big data works there is no such thing as irrelevant data in this case," said Peter Ludlow, a professor at Northwestern University who has written extensively about government surveillance. "Absolutely anything could be relevant to predicting an increased likelihood of criminal activity by someone."
Documents allegedly stolen by Snowden showed that U.S. tech companies, such as Google, Facebook and Microsoft, have collaborated with the NSA. The revelations brought dire warnings by experts that the industry would suffer heavy financial damage, particularly overseas.
So far, there has been no fallout, reports Reuters. Google, Microsoft and Amazon told the news agency they have seen no impact on their businesses. Amazon was not listed in the Snowden documents, but was seen as a likely victim of the exposure of NSA activity.
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