S.D. Codified Laws § 45-7-9

If any oil, gas, or mineral lease contains a statement of any contingency, the occurrence of which extends the lease for either a specified or an unspecified period of time, and that contingency has taken place, that lease may not be discharged or cancelled under the provisions of this chapter until the period of extension has run or until the contingency has ceased. Any such extension caused by reason of production shall be recorded by the lessee by filing an affidavit of production with the records of the property being leased in the office of the register of deeds.