To recap, there are a few different types of requests.
There are warrants/court orders, which everyone is familiar with.
Then there are NSLs. Those usually come from the FBI, and with a gag order. These can be included in transparency reports in aggregate, which is what the numbers provided by Google etc (and presumably dropbox) show.
"By law, NSLs can request only non-content information, such as transactional records, phone numbers dialled or sender or recipient email addresses. They also contain a gag order, preventing the recipient of the letter from disclosing that the letter was ever issued."
Worse than the NSL is the FISA order. These are not included in any "transparency reports", and they do not have to target specific users. They allow surveillance without a warrant. They don't even have to be for seeking evidence related to a crime, and can be issued just for "intelligence gathering".
"And it's even worse for FISA subpoenas, which can be used to force anyone to hand over anything in complete secrecy, and which were greatly strengthened by Section 215 of the USA PATRIOT Act. The government doesn't have to show probable cause that the target is a foreign power or agent — only that they are seeking the requested records "for" an intelligence or terrorism investigation. Once the government makes this assertion, the court must issue the subpoena."
In short, none of these transparency reports are worth anything, because they don't acknowledge FISA requests.
This right here is the contentious "Section 215", which is colloquially summarized as get everything, sort it later.
Its broad-sweeping and baseless nature is what's ruffling lots of feathers, and NSA's General Alexander praised it frequently in the much-reported congressional hearings from ~3 months ago.
The FISC has recently declassified their court opinion on it (they love it):
There are warrants/court orders, which everyone is familiar with.
Then there are NSLs. Those usually come from the FBI, and with a gag order. These can be included in transparency reports in aggregate, which is what the numbers provided by Google etc (and presumably dropbox) show.
"By law, NSLs can request only non-content information, such as transactional records, phone numbers dialled or sender or recipient email addresses. They also contain a gag order, preventing the recipient of the letter from disclosing that the letter was ever issued."
Worse than the NSL is the FISA order. These are not included in any "transparency reports", and they do not have to target specific users. They allow surveillance without a warrant. They don't even have to be for seeking evidence related to a crime, and can be issued just for "intelligence gathering".
"And it's even worse for FISA subpoenas, which can be used to force anyone to hand over anything in complete secrecy, and which were greatly strengthened by Section 215 of the USA PATRIOT Act. The government doesn't have to show probable cause that the target is a foreign power or agent — only that they are seeking the requested records "for" an intelligence or terrorism investigation. Once the government makes this assertion, the court must issue the subpoena."
In short, none of these transparency reports are worth anything, because they don't acknowledge FISA requests.