In NY, a dealer cannot sell a firearm without a serial number, so, if an older (pre1968 manufactured firearm) comes in to the shop the FFL is required by NYS law to affix a serial number. Dont know how that squares with the ATF. NY requires all kinds of $hit with guns now. Hell, dealers have to do a background check on muzzle loaders. When NY put that in place, they told dealers to use the 4473 to record it. ATF said hell no, we dont track muzzle loaders and using our form implies that we do. NY had to retract that and told dealers to "make up your own form"!!! Same thing with our ammunition background checks. NYS doesn't specify a form, they tell dealers to make up their own.