S.D. Codified Laws § 56-1-11
Current with legislation signed by the governor on or before 3/6/2024
In a guaranty of a contract, the terms of which are not then settled, it is implied that its terms shall be such as will not expose the guarantor to greater risks than he would incur under those terms which are most common in similar contracts at the place where the principal contract is to be performed.
SDCL 56-1-11