The snowden leaks among others show that most companies aware of PRISM ended up flat out lying about it. Either it's a type of NSL we haven't seen before or employees receive death threats, etc.
No, none of the companies lied about it. The companies worked with the FBI's Data Intercept Technology Unit. They would obviously have no knowledge of a dowstream data processing system like PRISM.
Couldn't an NSL have been served to datacenter operators, along with the notification of the attack, and the organisation's management simply be unaware?
