All i know is that the when i used to do it (full time for many years then for a few weekends last year) the PDQ machine didnt ask for those numbers. Thats not to say that the Merchant Services that we used could have asked us for those numbers if we rang up for a check which we never did becasue it takes so long.

They may have updated their systems since then. Someone want to try and buy something mail order and give them the wrong three numbers and see what happens?