The list you are talking about is probably a Mail-Via= Distribute in the header. Since you have a backbone listserv at your site, it will not cause additional network overhead. If you look at where the file originates, it is probably [log in to unmask] If you check your Listserv console spool at the time of delivery, it should have information indentifying that it was "distributing" and also whom it distributed to. /ahw