Exception

(A) Computation based on 12-month period If the taxpayer applies for the benefits of this paragraph and establishes the amount of this taxable income for the 12-month period described in subparagraph (B), computed as if that period were a taxable year and under the law applicable to that year, then the tax for the short period, computed under paragraph (1), shall be reduced to the greater of the following: (i) an amount which bears the same ratio to the tax computed on the taxable income for the 12-month period as the modified taxable income computed on the basis of the short period bears to the modified taxable income for the 12-month period; or (ii) the tax computed on the modified taxable income for the short period. The taxpayer (other than a taxpayer to whom subparagraph (B)(ii) applies) shall compute the tax and file his return without the application of this paragraph.

(B) 12-month period The 12-month period referred to in subparagraph (A) shall be— (i) the period of 12 months beginning on the first day of the short period, or (ii) the period of 12 months ending at the close of the last day of the short period, if at the end of the 12 months referred to in clause (i) the taxpayer is not in existence or (if a corporation) has theretofore disposed of substantially all of its assets.

(C) Application for benefits Application for the benefits of this paragraph shall be made in such manner and at such time as the regulations prescribed under subparagraph (D) may require; except that the time so prescribed shall not be later than the time (including extensions) for filing the return for the first taxable year which ends on or after the day which is 12 months after the first day of the short period. Such application, in case the return was filed without regard to this paragraph, shall be considered a claim for credit or refund with respect to the amount by which the tax is reduced under this paragraph.

(D) Regulations The Secretary shall prescribe such regulations as he deems necessary for the application of this paragraph.