Iowa Code § 554.7602
Unless a document of title was originally issued upon delivery of the goods by a person that did not have power to dispose of them, a lien does not attach by virtue of any judicial process to goods in the possession of a bailee for which a negotiable document of title is outstanding unless possession or control of the document is first surrendered to the bailee or the document's negotiation is enjoined. The bailee may not be compelled to deliver the goods pursuant to process until possession or control of the document is surrendered to the bailee or to the court. A purchaser of the document for value without notice of the process or injunction takes free of the lien imposed by judicial process.
Iowa Code § 554.7602
2007 Acts, ch 30, §42, 45, 46