S.D. Codified Laws § 21-22-28
The privacy of those who have established a court trust or other trust shall be protected in any court proceeding concerning the trust. Upon the filing of any petition, the instrument on which the trust is based, briefs, and the entire court file including a trust's inventory, statement filed by any fiduciary, annual verified report of a fiduciary, final report of a fiduciary, and all petitions relevant to trust administration and all court orders thereon shall be sealed upon filing and may not be made a part of the public record of the proceeding, but are available to the court, to the trustor, to any fiduciary, to any enforcer, to any beneficiary or the beneficiary's representative as provided in chapter 55-18, to their attorneys, and to such other interested persons as the court may order upon a showing of the need.
SDCL 21-22-28