https://www.atf.gov/rules-and-regula...espdf/download
Beginning on pg. 22, the AFT reclassifies all pistol grip shotguns as NFA items, completely blowing apart the 2014 determination.
Because these types of firearms were never designed to be fired from one hand, this rule, as described in the NPRM, does not apply to firearms commonly referred to as pistol grip shotguns.29 86 FR at 30828–29. The 2014 classification described above and any classification that provides that a pistol grip shotgun is not an NFA firearm is no longer valid or authoritative as of [INSERT DATE OF PUBLICATION IN THE FEDERAL REGISTER], and the firearm should be resubmitted to FATD for evaluation.