S.D. Codified Laws § 47-33-5
Subject to any provisions contained in its articles, which shall be applicable only to rights or options created or issued thereafter, a domestic public corporation may create and issue, by way of distributions to shareholders, as dividends or otherwise, rights or options entitling the holders thereof to purchase from the corporation shares of any class or series. Such rights or options shall be evidenced in such manner as the board shall approve and shall set forth the terms upon which, the time within which, and the price at which such shares may be purchased from the corporation upon the exercise of any such right or option. The terms and conditions of such rights or options may include, without limitation, provisions which adjust the option price or number of shares issuable under such rights or options in the event of an acquisition of shares or a reorganization, merger, consolidation, sale of assets or other occurrence involving the domestic public corporation, and restrictions or conditions that preclude or limit the entitlement, exercise or transfer of such rights or options by any person or persons who, after the date of the creation or issuance of such rights or options, acquires, obtains the right to acquire or offers to acquire, directly or indirectly, beneficial ownership of a specified number or percentage of the domestic public corporation's outstanding voting shares or other shares of the corporation, or that invalidate or void such rights or options held by any such person or persons. This section applies to rights or options created or issued before, on or after February 21, 1990.
SDCL 47-33-5