I mean... I guess... but wouldn't it make more sense to enforce all the unregistered SBRs first? And I'm sure there are 10's of 1000's. AFAIK nobody is even doing that. Also when I built my first SBR (and paid for professional engraving) 10 years ago I was told the stamps were optional. It's almost like they make this stuff as they go. /sarc/I don't intend to sell, but I don't want to be anywhere close to an ATF considered "noncompliant" weapon. The Form 1 stipulates in instruction number 2K, the requirements on marking the firearm. So, that is what I would do. I wouldn't want to be the one getting questioned by an ATF officer and my agreement start off with ... " on the internet..." lol