The NRA and SAF took them to court over that. The city at first denied they'd confiscated any firearms. Now they've agreed to return the guns they didn't confiscate. Don't know that they've actually returned any yet. I'm sure proving that a firearm is actually yours could be a bit difficult, since even if you had a bill of sale, there'd be a good chance that it would be a might soggy and hard to read. Of course there is no requirement to actually have one, I've got at least two firearms for which I never had one, and two others that I've had for over 20 years, and wouldn't have a clue where the BoS is, although I likely did keep it. Plus I've moved 5 times in that period, and things tend to get a bit scrambled when you move.