S.D. Codified Laws § 15-3-12 (2026)
Where it shall appear that there has been an actual continued occupation of premises under a claim of title exclusive of any other right, but not founded upon a written instrument, or a judgment, or decree, the premises so actually occupied, and no other, shall be deemed to have been held adversely.
Source: SDC 1939 & Supp 1960, § 33.0223.