Anybody claiming to own the copyright. It doesn't matter if the claim is legitimate; "safe harbor" means the time and effort wasted on copyright problems is lim

Anybody claiming to own the copyright. It doesn't matter if the claim is legitimate; "safe harbor" means the time and effort wasted on copyright problems is limited to hiding/restoring videos and forwarding a few legal notices between the claimant and alleged copyright infringe channel. The expensive parts like defending against potentially frivolous claims happens directly between the parties involved.