SDCL § 15-3-2: Seizin or possession within twenty years required for cause of action or defense based on title to real property.

No cause of action or defense to an action founded upon the title to real property or to rents or services out of the same, shall be effectual unless it appear that the person prosecuting the action or making the defense, or under whose title the action is prosecuted or the defense is made, or the ancestor, predecessor, or grantor of such person, was seized or possessed of the premises in question within twenty years before the committing of the act in respect to which such action is prosecuted or defense made.