(a) Passthrough inapplicable to section 34 credit. Section 1.1366-1(a) does not apply to any credit allowable under section 34 (relating to certain uses of gasoline and special fuels).

(b) Reduction in passthrough for tax imposed on built-in gains. For purposes of § 1.1366-1(a), if for any taxable year of the S corporation a tax is imposed on the corporation under section 1374, the amount of the tax imposed is treated as a loss sustained by the S corporation during the taxable year. The character of the deemed loss is determined by allocating the loss proportionately among the net recognized built-in gains giving rise to the tax and attributing the character of each net recognized built-in gain to the allocable portion of the loss.

(c) Reduction in passthrough for tax imposed on excess net passive income. For purposes of § 1.1366-1(a), if for any taxable year of the S corporation a tax is imposed on the corporation under section 1375, each item of passive investment income shall be reduced by an amount that bears the same ratio to the amount of the tax as the net amount of the item bears to the total net passive investment income for that taxable year.