Seems like a month doesn't go by that someone doesn't write that their dealer, or a seller, or a buyer, or somebody claims the SPAS12 is an NFA weapon. These are guns like machine guns, sawed-off shotguns, silencers, etc. Their transfer is carefully controlled by the BATF, and all such NFA weapons are listed in a special registry held by the NFA section of the BATF. They can only be transferred by special Type 3 dealers.
The problem is that proving something isn't is hard to do. The dealers and others claiming this to be true generally cannot be talked out of it.
So I will take a shot at it with my $10,000 challenge!!
Send me clear proof, preferably from the BATF, that the Franchi SPAS12 is an NFA weapon, and I'll send you $10,000!!
Go on, if you're so sure -- that $10,000 is waiting for you!