Iowa Code § 478.10

When any electric transmission line or lines are sold and transferred either by voluntary or judicial sale, the transfer shall carry with it the franchise under which the improvement is owned, maintained, or operated. If a transfer of such franchise is made before the improvement for which it was issued is constructed, in whole or in part, the transfer shall not be effective until the person, company, or corporation to whom it was issued files in the office of the utilities commission granting the franchise a notice in writing stating the date of the transfer and the name and address of the transferee.