There is a website called "Been Verified" that say's they can tell you if a person owns a weapon or not. I'm not a member, but I don't see how this is even possible, let alone accurate? Even a 4473 form isn't that traceable unless you are a member of law enforcement, and have the make and model of the gun, along with the serial number to trace back to the manufacturer. And even then, the gun could have been sold, stolen, or traded, and be on it's forth or fifth owner by then. Or not even exist for that matter. If it was a personal cash purchase, say at a gun show or flea market, or else from a private party, there is no way.
About the only way I could see this happening, is if it was a new gun purchased by credit card. I know credit card companies sell and or give out purchasing information to advertisers to see what people are into buying. But credit card numbers change all the time, and new accounts opened and old ones closed. That would also lead to a lot of dead ends. Also again, the gun could have been sold to another party. What am I missing here? Or is this straight up advertising bull$h!t?