The platforms are under no legal obligation to proactively seek out infringement and remove it, nor – most annoyingly of all – do they ever have to permanently remove an infringing work. “Notice and takedown” does not mean “notice and stay-down,” which results in an ongoing game of Whack-A-Mole for copyright owners who get a work removed, only to see it pop up again somewhere else on the internet… again, and again, and again… – Creative Future