S.D. Codified Laws § 58-27-57
Except with the director's consent, no insurer may have invested at any one time more than forty percent of its assets in the class of securities described in subdivisions 58-27-17(1), (2), (3), and (4) and in § 58-27-28, exclusive of obligations of the Student Loan Marketing Association, public utilities and securities described in §§ 58-27-103 and 58-27-104, and obligations guaranteed or insured by the United States government or any instrumentality or subdivision thereof or any state as defined in subdivision 58-1-2(17). For purposes of determining compliance with this section, the investments under subdivision 58-27-17(4) are limited to those mutual funds that are investing at least ninety percent in bonds defined in subdivisions 58-27-17(1), (2), and (3) and §§ 58-27-9 to 58-27-13, inclusive.
SDCL 58-27-57