Comment by alexkcd

Seems like this could be a common use case for pirates. Similar to how Megaupload or Fileshare worked a few years ago.

Sia's encryption doesn't protect the file hosts, if the uploader posts a link + decryption keys for pirated content to a public file sharing forum.

Does the take down notice go to everyone that hosts a fragment of the file? Who is liable if the uploader can't be traced?