It's theoretically possible the "buyer" doesn't register the gun in his name and does something using a gun still in you name, right?
I heard that's why we MUST be present to ENSURE the ownership transfer is done.
Theoretically you need need to notify HPD within 10 (?) days of selling a gun. (Like selling a car)
Hence the receipt with the buyers info and permit #.
Don’t need to be present.
I once went into HPD while registering a firearm and had a bunch of receipts from guns I sold a while before and asked Del Prado (tall bald guy with sense of humor) to check to make sure they were all registered by the new owners.
Del Prado gave me gas, but he checked and confirmed.
I miss the the old window gang.
I only sold to members of this forum who had multiple posts.
Edit: corrected By Flapp. It’s within 2 days. See below for cite by Flapp.
I was too lazy to look up the actual time frame Hence the question mark.