I don't see why folks are freaking out so much about "proving they owned "X" mags before the law changed". Whomever wants to accuse you can piss up a rope. Proof is the responsibility of the accuser, not the accused. INNOCENT UNTIL PROVEN GUILTY Good luck to them, proving when a mag was manufactured, much less sold without serial numbers. What you have is what you have. Any LEO that gets behind and fully supports this BS law and wants to cite a citizen for possessing an 11+rd magazine is a POS.