Basically, as I understand it, there is none. If you want to collect copyright infringement damages, you have to register for copyright, pay, and deposit a copy

Basically, as I understand it, there is none. If you want to collect copyright infringement damages, you have to register for copyright, pay, and deposit a copy. Otherwise you have a copyright on creation and don't need to deposit anything. The vast majority of created works are not deposited anywhere.