The ATF form 4473 (purchase record) is a paper record that gets stored at the local gun shop until they go out of business (upon which they all get sent to the

The ATF form 4473 (purchase record) is a paper record that gets stored at the local gun shop until they go out of business (upon which they all get sent to the ATF for scanning). It records the model, serial #, purchaser, etc. However, when you make a purchase the national instant background check (NICS) people do a national records search (to see if you're a felon, or other class of person not permitted to own a gun). The systems they query record who ask for information (security audit records, basically) so in those systems it will show that a NICS check was performed. Thus tying together the info that John Q. Public just bought a gun of some type. At the state & local level, several states require you to get a Firearm Owners ID (FOID) or purchase permit. The background checks for these are also an indicator that John Q. Public is a (probable) gun owner.