Originally Posted by denverbassman
You registered your guns?
If they were bought from an 01 FFL holder (a firearms dealer) rather than through a private party sale, then there is a paper trail associated with the serial number of said weapon along with his name, address and drivers license or ID and possibly social security number via form 4473 from the BATF, further the 01 dealer's bound book also has a record of the transaction. The bound book is what the BATF has the right to inspect from any 01 FFL holder at any time they desire.
Technically the NICS check is supposedly destroyed after an approval or denial, but the bound book is always around.