It seemed as if every large tech company in Silicon Valley was part of the U.S. surveillance program known as PRISM. At least, all of them except San Francisco-based Twitter.
Dropbox was apparently described in an NSA presentation as “coming soon.” Facebook, Apple, Google, Microsoft and Yahoo have all denied flatly that they allowed the government direct access to their servers or even heard of PRISM.
One of the reasons it might not be on the list is that a lot of its information is basically public. Twitter users don't have that much privacy data to mine as Facebook or Google. Although it does comply with government requests 57 percent of the time, the numbers are fairly low with only 1,009 requests in the last six months of 2012. Google had 21,389 requests in that same time frame and provided information 66 percent of the time.