S.D. Codified Laws § 47-16-56
If the name and address of any person entitled to receive the money or property mentioned in § 47-16-54 is shown on the records of the cooperative, and the money or property is of the value of fifty dollars or more, a notice shall be mailed or electronically transmitted to each person at the last known address. The notice shall describe the money or property referred to, state the name of each person who appears to be entitled to money or property as shown by the records of the cooperative, and state that the money or property will be forfeited to the cooperative six months from the date the notice is mailed or electronically transmitted unless the money or property is claimed and proper evidence of ownership is submitted within that time. The notice shall be dated and signed and mailed or electronically transmitted on behalf of the cooperative by its secretary or any other duly authorized individual.
SDCL 47-16-56