Because this is the only relevant case I can find or remember.
"The MPAA had presented evidence showing that the majority of content linked to on IsoHunt was infringing content, that the search engine was tuned to assist users in finding infringing works, and that Fung himself had made remarks suggesting the purpose of the site was to allow users to download infringing content."
https://en.m.wikipedia.org/wiki/IsoHunt