Well, one thing we know is that there is absolutely no penalty for violating British proof over here. I wonder whether all British proof marks are for real. I wish I had pictures of the fake Purdey I appraised for a U.S. dealer a few years ago. I loved that gun, it was very high quality, but the dealer had other plans for it and would not sell it to me for the low buck. Oh well. At least I'll recognize it if I ever see it again. The same appraisal involved a high, very high, grade Parker smallbore that is now happily in a collection. It was as badly faked as the Purdey, unfortunately.