27 CFR §40.408

No person shall commence operations under any bond, nor extend operations, until such person receives from the appropriate TTB officer notice of approval of the bond or an appropriate extension of coverage of the bond required under this subpart. Upon receipt of an approved bond or extension of coverage of bond from the appropriate TTB officer, such bond or extension of coverage of bond shall be retained by the manufacturer of cigarette papers and tubes in factory and shall be made available for inspection by any TTB officer upon request.