It's redacted but it's clear they subpoenaed the chans hosting and protecting Q. They were unable to gain any leads or any evidence on who Q Is. PBS/HBO NARRATIVE SHILLS BTFO.
Declassified FBI documents: https://vault.fbi.gov/qanon/qanon-part-01/view 4chan post: https://boards.4chan.org/pol/thread/428301127
I am pretty sure this was pointed out by Q at some point, and was also one of the Q proofs.
Yes.