S.D. Codified Laws § 55-4-27
No judgment shall be rendered in favor of the plaintiff in an action pursuant to § 55-4-25 unless he proves that within thirty days after the beginning of the action, or within such other period as the court may fix and more than thirty days prior to obtaining the judgment, he notified each of the beneficiaries known to the trustee who then had a present interest of the existence and nature of the action. Such notice shall be given by mailing copies thereof in postpaid envelopes addressed to such beneficiaries at their last known addresses. The trustee shall furnish the plaintiff a list of such beneficiaries and their addresses, within ten days after written demand therefor, and notification of the persons on such list shall constitute compliance with the duty placed on the plaintiff by this section.
SDCL 55-4-27