What Happens If You Only Send in One Fingerprint Card with Your ATF Application?

When you are applying for a tax stamp using the ATF 5320.1, ATF eForm 1, ATF 5320.4 or the ATF 5320.5, the individual or the responsible persons (if applying with a gun trust or as a legal entity) will need to send in two completed FD-258 fingerprint cards in with their tax stamp application.  What happens though, if you make a mistake and send in only one completed FD-258 fingerprint card?  According to the ATF the reason two FD-258 fingerprint cards are required is to ensure that the at least one of the FD-258 fingerprint cards is legible and that the second card is a backup card.  This means that your application should be processed as is if you accidentally only sent one FD-258 fingerprint card. You are still required to send in two FD-258 fingerprint cards for the following applications:  ATF 5320.1, ATF eForm 1, ATF 5320.4 or the ATF 5320.5.  But if you make a mistake there is leeway, but don't make it a habit.  You can purchase your FD-258 fingerprint cards here if you need them.