Mostly correct:
Background Check Records:
As of July 2004, approved purchaser information must be destroyed within 24 hours of the official NICS response to the dealer.20 This destruction requirement has been imposed in appropriations bills as part of the so-called “Tiahrt Amendments,” named after their chief proponent Rep. Todd Tiahrt (R-KS). As a result, ATF inspectors are no longer able to compare the information on file with the dealer to the information the dealer submitted to NICS.21 For more information about the Tiahrt Amendments, see our summary on Gun Trafficking & Straw Purchases.
http://smartgunlaws.org/maintaining-gun-sales-background-check-records-policy-summary/
Yes, the background database is supposed to be purged, but according to the Second Amendment Foundation, there is no penalty for not complying.
The Foundation added a penalty for noncompliance in an amendment to the last failed gun control law.
How do we know they are complying with the law?