SDCL § 29A-2-604: Failure of testamentary provision.

(a) A devise, other than a residuary devise, that fails for any reason becomes a part of the residue.

(b) A residuary devise that fails for any reason passes to the testator's heirs unless the residue is devised to two or more persons, in which event the failed devise passes to the other residuary devisee, or to other residuary devisees in proportion to the interest of each in the remaining part of the residue.

Source: SL 1995, ch 167, § 2-604.