(a) Definition. For purposes of subpart D (section 665 and following), part I, subchapter J, chapter 1 of the Internal Revenue Code of 1954, the term preceding taxable year does not include any taxable year to which such part I does not apply. See section 683 and regulations thereunder. Accordingly, the provisions of such subpart D may not, in general, be applied to any taxable year which begins before 1954 or ends before August 17, 1954. For example, if a trust (reporting on the calendar year basis) makes a distribution during the calendar year 1955 of income accumulated during prior years and the distribution exceeds the distributable net income of 1955, the excess distribution may be allocated under such subpart D to 1954, but it may not be allocated to 1953 and preceding years, since the Internal Revenue Code of 1939 applies to those years.

(b) Simple trusts subject to subpart D. An accumulation distribution may be properly allocated to a preceding taxable year in which the trust qualified as a simple trust (that is, qualified for treatment under subpart B (section 651 and following) of such part I). In such event, the trust is treated for such preceding taxable year in all respects as if it were a trust to which subpart C (section 661 and following) of such part I applies. An example of such a circumstance would be in the case of a trust (required under the trust instrument to distribute all of its income currently) which received in the preceding taxable year extraordinary dividends or taxable stock dividends which the trustee in good faith allocated to corpus, but which are subsequently determined to be currently distributable to the beneficiary. See section 643(a)(4) and § 1.643(a)-4. The trust would qualify for treatment under such subpart C for the year of distribution of the extraordinary dividends or taxable stock dividends, because the distribution is not out of income of the current taxable year and would be treated as other amounts properly paid or credited or required to be distributed for such taxable year within the meaning of section 661(a)(2). Also, in the case of a trust other than a foreign trust created by a U.S. person, the distribution would qualify as an accumulation distribution for the purposes of such subpart D if in excess of $2,000 and not excepted under section 665(b) and the regulations thereunder. In the case of a foreign trust created by a U.S. person, the distribution, regardless of the amount, would qualify as an accumulation distribution for the purposes of subpart D. For the purposes only of such subpart D, the trust would be treated as subject to the provisions of such subpart C for the preceding taxable year in which the extraordinary or taxable stock dividends were received and in computing undistributed net income for such preceding year, the extraordinary or taxable stock dividends would be included in distributable net income under section 643(a). The rule stated in the preceding sentence would also apply if the distribution in the later year were made out of corpus without regard to a determination that the extraordinary dividends or taxable stock dividends in question were currently distributable to the beneficiary.