(a) In general. Sections 1.1502-91 through 1.1502-96 and § 1.1502-98 apply to any testing date that is on or after June 25, 1999. Sections 1.1502-94 through 1.1502-96 also apply to a corporation that becomes a member of a group or ceases to be a member of a group (or loss subgroup) on or after June 25, 1999.

(b) Reattribution of losses under § 1.1502-36(d)(6). Section 1.1502-96(d) applies to reattributions of net operating loss carryovers, capital loss carryovers, and deferred deductions in connection with a transfer of stock to which § 1.1502-36 applies, and the election under § 1.1502-96(d)(5) (relating to an election to reattribute section 382 limitation) can be made with an election under § 1.1502-36(d)(6) to reattribute a loss to the common parent that is filed at the time and in the manner provided in § 1.1502-36(e)(5)(x).

(c) Application to section 163(j)—(1) Sections 1.382-2 and 1.382-5. To the extent the rules of §§ 1.1502-91 through 1.1502-99 effectuate the rules of §§ 1.382-2 and 1.382-5, the provisions apply with respect to ownership changes occurring on or after November 13, 2020. For loss corporations that have ownership changes occurring before November 13, 2020, see §§ 1.1502-91 through 1.1502-99 as contained in 26 CFR part 1, revised April 1, 2019. However, taxpayers and their related parties, within the meaning of sections 267(b) and 707(b)(1), may choose to apply the rules of §§ 1.1502-91 through 1.1502-99 to the extent they apply the rules of §§ 1.382-2 and 1.382-5, to ownership changes occurring during a taxable year beginning after December 31, 2017, as well as consistently applying the rules of the §§ 1.1502-91 through 1.1502-99 (to the extent they effectuate the rules of §§ 1.382-6 and 1.383-1), the section 163(j) regulations (as defined in § 1.163(j)-1(b)(37)), and, if applicable, §§ 1.263A-9, 1.263A-15, 1.381(c)(20)-1, 1.382-7, 1.469-9, 1.469-11, 1.704-1, 1.882-5, 1.1362-3, 1.1368-1, 1.1377-1, 1.1502-13, 1.1502-21, 1.1502-79, and 1.1504-4, to that taxable year.

(2) Sections 1.382-6 and 1.383-1. To the extent the rules of §§ 1.1502-91 through 1.1502-98 effectuate the rules of §§ 1.382-6 and 1.383-1, the provisions apply with respect to ownership changes occurring during a taxable year beginning on or after November 13, 2020. For the application of these rules to an ownership change with respect to an ownership change occurring during a taxable year beginning before November 13, 2020, see §§ 1.1502-91 through 1.1502-99 as contained in 26 CFR part 1, revised April 1, 2019. However, taxpayers and their related parties, within the meaning of sections 267(b) and 707(b)(1), may choose to apply the rules of §§ 1.1502-91 through 1.1502-99 (to the extent that those rules effectuate the rules of §§ 1.382-6 and 1.383-1), to ownership changes occurring during a taxable year beginning after December 31, 2017, so long as the taxpayers and their related parties consistently apply the rules of 1.1502-91 through 1.1502-99 (to the extent that those rules effectuate the rules of §§ 1.382-2 and 1.382-5), the section 163(j) regulations (as defined in § 1.163(j)-1(b)(37)), and, if applicable, §§ 1.263A-9, 1.263A-15, 1.381(c)(20)-1, 1.382-7, 1.469-9, 1.469-11, 1.704-1, 1.882-5, 1.1362-3, 1.1368-1, 1.1377-1, 1.1502-13, 1.1502-21, 1.1502-36, 1.1502-79, and 1.1504-4, to a taxable year beginning after December 31, 2017.