S.D. Codified Laws § 11-7-25
No commissioner or employee of a commission may voluntarily acquire any interest, direct or indirect, in any project or in any property included or planned to be included in any project, nor shall he have any interest, direct or indirect, in any contract or proposed contract for materials or services to be furnished or used in connection with any project. If any commissioner or employee of a commission previously owned or controlled an interest, direct or indirect, in any property included or planned to be included in any project, or presently has such interest, he immediately shall disclose such interest in writing to the commission, and such disclosure shall be entered upon the minutes of the commission. A violation of this section is a Class 2 misdemeanor.
SDCL 11-7-25