S.D. Codified Laws § 16-19-79
A disbarred or suspended attorney shall promptly notify, or cause to be notified, by certified mail, return receipt requested, each client who is involved in pending litigation or administrative proceedings, and each attorney for an adverse party in such cases, of the disbarment or suspension and the attorney's consequent inability to act as an attorney after the effective date of the disbarment or suspension. The notice to be given to the client shall advise the client of the importance of prompt substitution of another attorney of the client's own choice.
In the event the client does not obtain substitute counsel before the effective date of the disbarment or suspension, the disbarred or suspended attorney shall move in the court or agency in which the proceeding is pending for leave to withdraw.
The notice to be given to the attorney or attorneys for an adverse party shall state the mailing address and place of residence of the client of the disbarred or suspended attorney.
SDCL 16-19-79