It seems to me that they are deliberately conflating "infringing someone's copyright" and "using to infringe someone's copyright" - there's a difference between "you have my copyrighted code in your github" and "you are providing software that can be used for copying my movie" - the first is what DMCA notices are for, not the second
Your last sentence is not true. The DMCA notice can be used for anything that the DMCA covers. One thing in the DMCA is:
> linking users to an online location containing [...] infringing activity
Extremely broad, but a link to a file sharing site with infringing content is also infringing. The DMCA notice can be used against the site containing the link.
That’s a good question. A strict reading would imply a single one, and would mean that only TPB would be infringing because they’re the ones “linking” to the content (they don’t host it). But it could easily be construed to mean a link to TPB is also infringing.
The problem with the DMCA is that it’s so broadly worded with not enough words defined. What is the definition of “linking”? After a quick skim, I couldn’t find it. Are only hyperlinks (<a> tags) counted? Or are magnet “links” counted (despite not taking you to the content, but telling you the hashes of the content)? There’s no clear answer.
Notice-and-takedown provisions are not just for things that actually infringe copyright, and the "DMCA notice" part may be an extremely easy misclassification of the letter sent to GitHub. More specifically, notice-and-takedown is for user-submitted content that is illegal or tortious to knowingly distribute. Copyrighted content is the main offender here, but there are other categories, especially "anti-circumvention" tools illegal under other provisions of the DMCA.
