Iowa Admin. Code r. 199-18.3
All records kept pursuant to any rules of the commission that are of a general corporate nature or otherwise pertain to the utility's operations as a whole shall be made available for examination by the commission during normal business hours, unless otherwise authorized by the commission. Upon receipt by a utility of a formal request in writing from the commission for records or information pertaining to records required by any commission rule, the utility shall provide the requested information to the commission within 15 days of receiving the written request from the commission unless the utility files an objection to the request or a request for an extension of time within seven days of the utility's receipt of the information request. The objection or request for extension of time shall be filed in writing and state the concise grounds for relief. If the commission finds that the objection or request for extension of time does not have merit, the information originally requested shall be provided immediately upon receiving notice of the commission's decision.
Iowa Admin. Code r. 199-18.3