(a) In general. If the separate share rule of section 663(c) is applicable for any taxable year of a trust, subpart D is applied as if each share were a separate trust except as provided in paragraph (c) of this section and in § 1.668(a)-1A(c). Thus, the amounts of an “accumulation distribution”, “undistributed net income”, “undistributed capital gain”, and “capital gain distribution” are computed separately for each share.

(b) Allocation of taxes—undistributed net income. The “taxes imposed on the trust attributable to the undistributed net income” are allocated as follows:

(1) There is first allocated to each separate share that portion of the “taxes imposed on the trust attributable to the undistributed net income” (as defined in § 1.665(d)-1A(b)), computed before the allowance of any credits under section 642(a), that bears the same relation to the total of such taxes that the distributable net income of the separate share bears to the distributable net income of the trust, adjusted for this purpose as follows:

(i) There is excluded from distributable net income of the trust and of each separate share any tax-exempt interest, foreign income of a foreign trust, and excluded dividends, to the extent such amounts are included in distributable net income pursuant to section 643(a) (5), (6), and (7); and

(ii) The distributable net income of the trust is reduced by any deductions allowable under section 661 for amounts paid, credited, or required to be distributed during the taxable year, and the distributable net income of each separate share is reduced by any such deduction allocable to that share.

(2) The taxes so determined for each separate share are then reduced by that portion of the credits against tax allowable to the trust under section 642(a) in computing the “taxes imposed on the trust” that bears the same relation to the total of such credits that the items of distributable net income allocable to the separate share with respect to which the credit is allowed bear to the total of such items of the trust.

(c) Allocation of taxes—undistributed capital gain. The “taxes imposed on the trust attributable to undistributed capital gain” are allocated as follows:

(1) There is first allocated to each separate share that portion of the “taxes imposed on the trust attributable to undistributed capital gain” (as defined in § 1.665(d)-1A(c)), computed before the allowance of any credits under section 642(a), that bears the same relation to the total of such taxes that the undistributed capital gain (prior to the deduction of taxes under section 665(c)(2)) of the separate share bears to the total such undistributed capital gain of the trust.

(2) The taxes so determined for each separate share are then reduced by that portion of the credits against tax allowable to the trust under section 642(a) in computing the “taxes imposed on the trust” that bears the same relation to the total of such credits that the capital gain allocable to the separate share with respect to which the credit is allowed bear to the total of such capital gain of the trust.

(d) Termination of a separate share. (1) If upon termination of a separate share, an amount is properly paid, credited, or required to be distributed by the trust under section 661(a)(2) to a beneficiary from such share, an accumulation distribution will be deemed to have been made to the extent of such amount. In determining the distributable net income of such share, only those items of income and deduction for the taxable year of the trust in which such share terminates, properly allocable to such share, shall be taken into consideration.

(2) No accumulation distribution will be deemed to have been made upon the termination of a separate share to the extent that the property constituting such share, or a portion thereof, continues to be held as a part of the same trust. The undistributed net income, undistributed capital gain, and the taxes imposed on the trust attributable to such items, if any, for all preceding taxable years (reduced by any amounts deemed distributed under sections 666(a) and 669(a) by reason of any accumulation distribution of undistributed net income or undistributed capital gain in prior years or the current taxable year), which were allocable to the terminating share, shall be treated as being applicable to the trust itself. However, no adjustment will be made to the amounts deemed distributed under sections 666 and 669 by reason of an accumulation distribution of undistributed net income or undistributed capital gain from the surviving share or shares made in years prior to the year in which the terminating share was added to such surviving share or shares.

(3) The provisions of this paragraph may be illustrated by the following example: