Not sure, but I thought that in order to be classified as a pistol and avoid the dreaded SBR designation, it couldn't have a stock of any kind. Folding or otherwise. I've seen other guns offered for sale that have their folding stocks welded in the folded position so that it could be classified as a pistol.
O...how I wish I lived in a state that would like such a pistol..although I'm not sure if it's illegal in NY but I assume only cause well... It's New York and New York City dictates the show for us up State folks.. I'm jealous, so buy one for me!