Reg. § 301.6501(g)-1 Certain income tax returns of corporations.
(a) Trusts or partnerships If a taxpayer determines in good faith that it is a trust or partnership and files a return as such under subtitle A of the Code, and if the taxpayer is later held to be a corporation for the taxable year for which the return was filed, such return shall be deemed to be the return of the corporation for the purpose of section .
(b) Exempt organizations If a taxpayer determines in good faith that it is an exempt organization and files a return as such under section , and if the taxpayer is later held to be a taxable organization for the taxable year for which the return was filed, such return shall be deemed to be the return of the organization for the purpose of section .
(c) DISC If a corporation determines in good faith that it is a DISC (as defined in section ) for a taxable year and files a return as such pursuant to section , and if the corporation is thereafter held to be a corporation which is not a DISC for the taxable year for which the return was filed, then—
(1) Such return shall be deemed to be the return of the corporation for the purpose of section .
(2) Such return if filed within the time required by section for filing a DISC return shall be deemed to be filed within the time required by section for filing of a return by a corporation which is not a DISC, and
(3) Interest on underpayment and overpayments allowed by chapter 67 of the Code and additions to the tax, additional amounts and assessable penalties allowed by chapter 68 of the Code, when determined by reference to the time for filing of a return, shall be determined by reference to the time required by section for filing of a return by a DISC.
[32 FR 15241, Nov. 3, 1967, as amended by T.D. 7533, 43 FR 6604, Feb. 15, 1978]