(a) Requirement to backup withhold. Withholding under section 3406 applies to a window transaction (as defined in paragraph (b) of this section) only if the payee does not furnish a taxpayer identification number to the payor in the manner required in paragraph (c) of this section or furnishes an obviously incorrect number as described in § 31.3406(h)-1(b)(2). Withholding does not apply to a window transaction even though the Internal Revenue Service notifies the payor of the payee's incorrect taxpayer identification number under section 3406(a)(1)(B) or of notified payee underreporting under section 3406(a)(1)(C). The payee in a window transaction is not required to certify under penalties of perjury that the payee is not subject to withholding due to notified payee underreporting (as described in § 31.3406(d)-2(b)(2)).

(b) Window transaction defined. Window transaction means a payment of interest with respect to any of the following obligations:

(1) An interest coupon in bearer form that is subject to taxation (i.e., other than exempt interest described in § 1.6049-5(b)(1)(ii) of this chapter);

(2) A United States savings bond; or

(3) A discount obligation having a maturity at issue of one year or less, including commercial paper and bankers' acceptances that are in definitive form (i.e., evidenced by a paper document other than a confirmation receipt) but not including short-term government obligations (as defined in section 1271(a)(3)(B)).

(c) Manner of furnishing taxpayer identification number in the case of a window transaction. A payee must furnish the payee's taxpayer identification number to the payor with respect to a window transaction either orally or in writing at the time that the window transaction occurs. See § 31.3406(g)-3(c)(1)(i), which provides that a payee may not claim the payee is awaiting receipt of a taxpayer identification number with respect to a window transaction. The payee is not required to certify, under penalties of perjury, that the taxpayer identification number provided is correct.