Iowa Code § 587.5
No judgment or decree purporting to set aside any will or the provisions of any will, or to place any construction upon any will or terms of any will, or to aid in carrying out the provisions of any will, and no contract or agreement purporting to be a settlement of any suit or action to set aside any will or the terms of any will, or to place any construction upon any will or any of the terms thereof, shall be held ineffectual, void, or insufficient because the records fail to show proper service of notice on all parties interested, that persons under disability affected by the action were not properly served with notice or represented by guardian or guardian ad litem, either in suit, action, or in a settlement thereof, that all persons interested participated in the settlement, or that any other provisions of law had been complied with which are necessary to make a valid decree, judgment, or settlement; provided more than ten years had elapsed since the judgment, decree, contract, or agreement was filed, entered, or placed on record in the county where the real estate affected thereby is situated. Said decree, judgment, contract, or agreement shall be conclusive evidence of the right, title, or interest it purports to establish or adjudicate insofar as it affects the title to such real estate, and said proceedings therein are hereby made legal and effectual the same as though all provisions of law had been complied with in the obtaining of said decree, judgment, or execution of said contract or agreement, and any judgment, decree, contract, or agreement such as above described which is now of record less than ten years in the county in which the real estate is situated shall, at the expiration of ten years from date of filing, entering, or recording thereof, have the same force and effect as is above given to those now in effect more than ten years.
Iowa Code § 587.5