Not a filibuster but a run of the mill speech that will end when debate on the trade bill ends.

.@jaketapper if there’s a set time limit, it’s not a filibuster. His speech will end when the time limit expires on the trade bill debate.

— lawhawk (@lawhawk) May 20, 2015

Not exactly a difficult concept. A filibuster happens when you prevent action on a piece of legislation. Paul’s simply using all the allotted time on another bill (trade bill) to harp on provisions in an unrelated bill (Patriot Act).