S.D. Codified Laws § 10-50-28
Each such nonresident person, other than a foreign corporation which has complied with the provisions of the statutes of this state relative to foreign corporations, shall, in writing, appoint the secretary of state and his successors in office to be his attorney, such appointment to be made, acknowledged, and filed in the manner prescribed in the statutes relative to foreign corporations. Service upon said attorney shall be sufficient service upon any such nonresident person, whether a foreign corporation which has complied with the provisions of the statutes relating to foreign corporations or not, and may be made by leaving a true copy of the process with the secretary of state or at his office. When legal process against any such nonresident person shall be served upon the secretary of state he shall notify such nonresident person in the manner specified in the statutes relating to service of process upon foreign corporations licensed to do business in this state, and shall collect the fee as therein specified.
SDCL 10-50-28