SDCL § 10-18-1.1: Time allowed for abatement or refund of invalid, inequitable or unjust tax.

If the board of county commissioners is satisfied beyond a doubt that the assessment of real property described in an application for abatement or refund under the provisions of § 10-18-1 is invalid, inequitable, or unjust, the board, if application is filed no later than the first day of November of the fourth year after which such taxes would have become delinquent, may abate or refund any part thereof in excess of a just, fair, and equitable assessment if such application for correction complies with requirements of this chapter.