Earlier quoted context omitted.
With creative common and GPL there is a fairly common practice that work include multiple authors and rights holders. When a single user uploads such work to a hosting provider, the permission given to the provider will be limited to the permission that the user had. They can't give out permissions that they themselves do not have. It is a similar case when a single user uploads a movie or game to a pirate torrent si…
> They can't give out permissions that they themselves do not have. Then, chances are, it's technically illegal to upload those other contributors' code, although if that code is contributed via GitHub itself then the code in the pull request has already been licensed to GH. It boils down to copyright/DMCA not requiring that hosting providers ensure the code people say they have the rights to is valid at submission,…
In the US what it will be is good evidence to support a claim by GitHub that they were an "innocent infringer"--someone who did not know they were infringing and had no reason to believe that they were.
What that does is in the case where the plaintiff seeks statutory damages (which they almost certainly will¹) is lower the lower limit. Statutory damages are normally $750-30000 (amount determined by the court). If a defendant proves they are an innocent infringer that lower limit drops to $200. If the plaintiff can prove that the infringement was "willful" the upper limit goes up to $150000.
Statutory damages are per work infringed, not per infringement, so we aren't talking $200 or so multiplied by the number of copies GitHub distributed. We are talking of a likely award of $200 or so total (plus maybe attorney fees).
¹It is usually way too hard to determine actual monetary damages in cases like this, and actual damages are likely to be quite low anyway, so plaintiffs almost certainly will go for statutory damages.