(a) Except for a disclaimer governed by § 607 or § 608 of this title, the following rules apply to a disclaimer of an interest in property:
(1) If the interest was created by an instrument, the disclaimer takes effect as of the time the instrument creating the interest becomes irrevocable, and the disclaimed interest passes as follows:
a. If the instrument creating the interest includes a provision providing for the disposition of the interest, if the interest is disclaimed, or of disclaimed interests in general, the interest passes according to the provisions in the instrument governing the disposition of the disclaimed interest.
b. If the instrument creating the interest does not include a provision described in paragraph (a)(1)a. of this section, if the disclaimant is an individual, the disclaimed interest passes as if the disclaimant had died immediately before the time of distribution, and if the disclaimant is not an individual, the disclaimed interest passes as if the disclaimant did not exist at the time of distribution.
c. If the disclaimant is an individual, and if, by law or under the provisions of the instrument creating the interest, the descendants of the disclaimant, or the descendants of any other individual, if applicable, would share in the disclaimed interest by any method of representation had the disclaimant died immediately before the time of distribution, the disclaimed interest passes only to the descendants of the disclaimant, or the descendants of the other applicable individual, who survive the time of distribution.
(2) If the interest in property being disclaimed arose under the law of intestate succession, the disclaimer takes effect as of the time of the intestate's death.
(3) If a disclaimant disclaims an interest in property preceding the future interest or interests of any person or persons in such property:
a. A future interest held by a person other than the disclaimant takes effect as if the disclaimant had died or ceased to exist immediately before the time of distribution.
b. A future interest in the property held by the disclaimant that the disclaimant retained when disclaiming the preceding interest will not accelerate the disclaimant's possession or enjoyment of the future interest retained by the disclaimant.
(b) For the purposes of this section:
(1) “Future interest” means an interest that takes effect in possession or enjoyment, if at all, later than the time of the creation of the interest.
(2) “Time of distribution” means the time when a disclaimed interest would have taken effect in possession or enjoyment.