Doggone it, they have one of mine, too, a short one shot. Guess I'll be filing a complaint, as well! I heard about this earlier via Ao3 on Twitter, but must have searched wrong because I didn't find anything of mine at the time. It's very upsetting for us who have had works stolen -- in addition, I am an admin of a fanfic archive that is transferring all the works housed there to an archive at Ao3 before shutting down, and this could be a problem for stories that don't have accessible authors who can file complaints. Hopefully, Ao3 will be able to figure out how to combat this without curtailing access to proper users of the site.