Tariffs filed

1. Every public utility shall file with the commission tariffs showing the rates and charges for its public utility services and the rules and regulations under which such services were furnished, on April 1, 1963, which rates and charges shall be subject to investigation by the commission as provided in section 476.3, and upon such investigation the burden of establishing the reasonableness of such rates and charges shall be upon the public utility filing the same. These filings shall be made under such rules as the commission may prescribe within such time and in such form as the commission may designate. In prescribing rules and regulations with respect to the form of tariffs and any other regulations, the commission shall, in the case of public utilities subject to regulation by any federal agency, give due regard to any corresponding rules and regulations of such federal agency, to the end that unnecessary duplication of effort and expense may be avoided so far as reasonably possible. Each public utility shall keep copies of its tariffs open to public inspection under such rules as the commission may prescribe. 2. No later than January 1, 2015, a telephone utility is required to file tariffs as provided in this section only for such wholesale services as may be specified by the commission. 3. Every rate, charge, rule, and regulation contained in any filing made with the Iowa state commerce commission on or prior to July 4, 1963, shall be effective as of such date, subject, however, to investigation as provided in this chapter. If any such filing is made prior to the time the Iowa state commerce commission prescribes rules, and if such filing does not comply as to form or substance with such rules, then the public utility which filed the same shall, within a reasonable time after the adoption of such rules, make a new filing or filings complying with such rules, which new filing or filings shall be deemed effective as of July 4, 1963.