26 CFR § 1.312-10 - Allocation of earnings in certain corporate separations.
(a) If one corporation transfers part of its assets constituting an active trade or business to another corporation in a transaction to which section 368(a)(1)(4) applies and immediately thereafter the stock and securities of the controlled corporation are distributed in a distribution or exchange to which section 355 (or so much of section 356 as relates to section 355) applies, the earnings and profits of the distributing corporation immediately before the transaction shall be allocated between the distributing corporation and the controlled corporation. In the case of a newly created controlled corporation, such allocation generally shall be made in proportion to the fair market value of the business or businesses (and interests in any other properties) retained by the distributing corporation and the business or businesses (and interests in any other properties) of the controlled corporation immediately after the transaction. In a proper case, allocation shall be made between the distributing corporation and the controlled corporation in proportion to the net basis of the assets transferred and of the assets retained or by such other method as may be appropriate under the facts and circumstances of the case. The term net basis means the basis of the assets less liabilities assumed or liabilities to which such assets are subject. The part of the earnings and profits of the taxable year of the distributing corporation in which the transaction occurs allocable to the controlled corporation shall be included in the computation of the earnings and profits of the first taxable year of the controlled corporation ending after the date of the transaction.
(b) If a distribution or exchange to which section 355 applies (or so much of section 356 as relates to section 355) is not in pursuance of a plan meeting the requirements of a reorganization as defined in section 368(a)(1)(D), the earnings and profits of the distributing corporation shall be decreased by the lesser of the following amounts:
(1) The amount by which the earnings and profits of the distributing corporation would have been decreased if it had transferred the stock of the controlled corporation to a new corporation in a reorganization to which section 368(a)(1)(D) applied and immediately thereafter distributed the stock of such new corporation or,