Comment by vasco

12 hours ago

Plus afaik you can add any co-author you want without validation. So you can ban everyone on arxiv with one paper with one sentence.

As I mentioned in another thread:

To be a coauthor on a preprint that you have not submitted, you have to actively "claim" it (using a password given to the author who submitted). It's on you to double-check before claiming.

I surely hope that only "confirmed" coauthors will get the ban, it's only logical.