26 CFR § 48.4052-1 - Heavy trucks and trailers; certification requirement.
(a)In general. Tax is not imposed by section 4051 on the sale of an article for resale or leasing in a long-term lease if, by the time of sale, the seller has in good faith accepted from the buyer a statement that the buyer executed in good faith and that is in substantially the same form, and subject to the same conditions, as the certificate described in § 145.4052-1(a)(6) of this chapter, except that the certificate must be signed under penalties of perjury and need not refer to Form 637 or include a registration number.
(c)Effective date. This section is applicable after June 30, 1998. In addition, tax is not imposed on a sale occurring after December 31, 1997, and before July 1, 1998, if the conditions of paragraph (a) of this section are satisfied.