S.D. Codified Laws § 47-1A-202.3
Articles of incorporation--Extrinsic facts
Provisions of the articles of incorporation may be made dependent upon facts objectively ascertainable outside the articles of incorporation in accordance with §§ 47-1A-120.1 to 47-1A-120.3 , inclusive.
Source: SL 2005, ch 239, § 31.