S.D. Codified Laws § 22-25A-1

For the purposes of this chapter, the term, bet or wager, means to directly or indirectly take, receive, or accept money or any valuable thing with the understanding or agreement that the money or valuable thing will be paid or delivered to a person if the payment or delivery is contingent upon the result of a race, contest, or game or upon the happening of an event not known to be certain. Bet or wager does not include the purchase, sale, or trade of securities or commodities under state or federal law.