(2)Decedents dying after September 30, 1963 and before October 4, 1966. This paragraph (b)(2) applies in the case of a disclaimer of property passing to one other than the surviving spouse from a decedent dying after September 30, 1963 and before October 4, 1966. If, as a result of the disclaimer by the disclaimant, the surviving spouse is entitled to receive the disclaimed property interest, then such interest shall, for the purposes of this paragraph (b)(2), be considered as passing from the decedent to the surviving spouse if the following conditions are met. First, the interest disclaimed was bequeathed or devised to the disclaimant. Second, the disclaimant disclaimed all bequests and devises under the will before the date prescribed for the filing of the estate tax return. Third, the disclaimant did not accept any property under the bequest or devise before making the disclaimer. The interests passing by disclaimer to the surviving spouse under this paragraph (b)(2) are to qualify for the marital deduction only to the extent that, when added to any other allowable marital deduction without regard to this paragraph (b)(2), they do not exceed the greater of the deductions which would be allowable for the marital deduction without regard to the disclaimer if the surviving spouse exercised the election under State law to take against the will, or an amount equal to one-third of the decedent's adjusted gross estate. If the disclaimer does not satisfy the requirements of this paragraph (b)(2), the property is treated as passing from the decedent to the person who made the disclaimer, in the same manner as if the disclaimer had not been made.