Iowa Code § 99.4: Owner defined — notice.

The person in whose name the real estate affected by the action stands on the books of the county auditor, for the purposes of taxation, shall be presumed to be the owner thereof, and in case of unknown persons having or claiming any ownership, right, title, or interest in property affected by the action, such may be made parties to the action by designating them in the notice and petition as “all other persons unknown claiming any ownership, right, title, or interest in the property affected by the action” and service thereon may be had by publishing such notice in the manner prescribed for the publication of original notices in ordinary actions.