(a) In general.--A disclaimer relates back for all purposes to the date of the death of the decedent or the effective date of the inter vivos transfer or third-party beneficiary contract as the case may be. The disclaimer shall not in any way diminish the interest of any person other than the disclaimant in such person's own right under the instrument creating the disclaimed interest or under the intestate laws nor diminish any interest to which such person becomes entitled under subsection (b) by reason of the disclaimer.

(b) Rights of other parties.--Unless a testator or donor has provided for another disposition, the disclaimer shall, for purposes of determining the rights of other parties, be equivalent to the disclaimant's having died before the decedent in the case of a devolution by will or intestacy or before the effective date of an inter vivos transfer, or third-party beneficiary contract, except that, when applying section 2104(1) (relating to rules of succession) or analogous provisions of a governing instrument, the fact that the disclaimant actually survived shall be recognized in determining whether other parties take equally or by representation, and except that if, as a result of a disclaimer, property passes to a fund in which the disclaimant has an interest or power which he has not disclaimed, the disclaimant shall retain his interest or power in the fund as augmented by the disclaimed property.

(c) Powers of appointment.--In applying this section to an interest that would have devolved by reason of the exercise of a power of appointment, the person exercising the power shall be regarded as the decedent or transferor, as the case may be.

(d) Rights of creditors of disclaimant.--Nothing in this section shall determine the effect of a disclaimer upon the rights of creditors of the disclaimant.