This proposed rule would update the definition of importation in the implementing regulations for the Gun Control Act (GCA) and the National Firearms Act (NFA). Specifically, the proposed rule would modify the definition to create an exclusion from import requirements for items brought into customs-bonded warehouses (CBWs) (in addition to the existing exclusion for foreign-trade zones (FTZs)). The proposed rule would also expand permissible activities that federal firearms licensees (FFLs) may perform on items in FTZs and CBWs, by removing the qualification that items may be brought into these spaces only for storage.