26 CFR § 20.2056(b)-2 - Marital deduction; interest in unidentified assets.
(a) In general. Section 2056(b)(2) provides that if an interest passing to a decedent's surviving spouse may be satisfied out of assets (or their proceeds) which include a particular asset that would be a nondeductible interest if it passed from the decedent to his spouse, the value of the interest passing to the spouse is reduced, for the purpose of the marital deduction, by the value of the particular asset.
(b) Application of section 2056(b)(2). In order for section 2056(b)(2) to apply, two circumstances must coexist, as follows:
(1) The property interest which passed from the decedent to his surviving spouse must be payable out of a group of assets included in the gross estate. Examples of property interests payable out of a group of assets are a general legacy, a bequest of the residue of the decedent's estate or of a proportion of the residue, and a right to a share of the corpus of a trust upon its termination.
(2) The group of assets out of which the property interest is payable must include one or more particular assets which, if passing specifically to the surviving spouse, would be nondeductible interests. Therefore, section 2056(b)(2) is not applicable merely because the group of assets includes a terminable interest, but would only be applicable if the terminable interest were nondeductible under the provisions of § 20.2056(b)-1.
(c) Interest nondeductible if circumstances present. If both of the circumstances set forth in paragraph (b) of this section are present, the property interest payable out of the group of assets is (except as to any excess of its value over the aggregate value of the particular asset or assets which would not be deductible if passing specifically to the surviving spouse) a nondeductible interest.
(d) Example. The application of this section may be illustrated by the following example: