Gun serial #’s are stored in FFL’s acquisitions and dispositions book (A&D bound book) and ATF form 4473. Someone claiming that a gun is stolen based on a serial # they saw from a picture, would initiate a chain reaction. Starting with local law enforcement, ATF, manufacturer of firearm, wholesaler (or dealer direct), 1st dealer it was sold too, 2nd dealer and or private citizen that bought it on ATF form 4473.
When it turns out that the guy is lying about being the owner of the gun, I am sure the ATF will apply it’s full governmental weight and authoritie
directly on his neck, for filing false reports and wasting their time.