S.D. Codified Laws § 47-14A-10
A trustee of a business trust may be served with process in the manner prescribed in § 47-14A-11 in all civil actions or proceedings brought in the state involving or relating to the activities of the business trust or a violation by a trustee of a duty to the business trust, or any beneficial owner, whether or not the trustee is a trustee at the time suit is commenced. Every resident or nonresident of the state who accepts election or appointment or serves as a trustee of a business trust shall, by such acceptance or service, be deemed thereby to have consented to the appointment of the South Dakota trustee or registered agent of such business trust required by § 47-14A-30 (or, if there is none, the secretary of state) as such person's agent upon whom service of process may be made as provided in this section. Such acceptance or service shall signify the consent of such trustee that any process if so served shall be of the same legal force and validity as if served upon such trustee within the state and such appointment of such South Dakota trustee or registered agent (or, if there is none, the secretary of state) shall be irrevocable.
SDCL 47-14A-10