All deeds executed more than ten years earlier, by a court or the chairperson of the board of supervisors of a county, and to which the officer executing the deed has failed or omitted to affix the county seal, and all deeds where the clerk has failed or omitted to countersign when required so to do, are legalized and valid as though the law had in all respects been fully complied with.
Iowa Code § 589.2
84 Acts, ch 1090, §2; 91 Acts, ch 183, §12