Mo. Rev. Stat. § 14.030

When a certificate of discharge of any tax lien issued by the collector of internal revenue or other proper officer is filed in the office of the recorder or clerk where the original notice of lien is filed, said recorder or clerk shall enter the same with the date of filing in said federal tax lien index on the line where the notice of the lien so discharged is entered and permanently attach the original certificate of discharge to the original notice of lien.