27 C.F.R. § 20.36
(a) When any form or document prescribed by this part is required to be executed under penalties of perjury, the dealer or user or other authorized person shall:
(b) When the required document already bears a perjury declaration, the dealer or user or other authorized person shall sign the document.
(26 U.S.C. 6065)
[T.D. ATF-199, 50 FR 9162, Mar. 6, 1985, as amended by T.D. ATF-332, 57 FR 40849, Sept. 8, 1992]