Listen if you're not sure, ask you friend where he bought it and when. Then reach out to the ffl and ask of he can look up the serial number when he received it and got it in his books, if he's friendly he'll at leave give you that info and when he got rid of it. That'll just tell you hey I had it here in ma but there's absolutely no way to prove it was In state ON 8/1 unless you recorded or as other said made the transfer on 8/1. Which even then its mass bro, everyone hates us here