(a) Duty of holding companies to keep

Every registered holding company and every subsidiary company thereof shall make, keep, and preserve for such periods, such accounts, cost-accounting procedures, correspondence, memoranda, papers, books, and other records as the Commission deems necessary or appropriate in the public interest or for the protection of investors or consumers or for the enforcement of the provisions of this chapter or the rules, regulations, or orders thereunder.

(b) Duty of affiliates to keep

Every affiliate of a registered holding company or of any subsidiary company thereof, or of any public-utility company engaged in interstate commerce or not so engaged, shall make, keep, and preserve for such periods, such accounts, cost-accounting procedures, correspondence, memoranda, papers, books, and other records relating to any transaction of such affiliate which is subject to any provision of this chapter or any rule, regulation, or order thereunder, as the Commission deems necessary or appropriate in the public interest or for the protection of investors or consumers or for the enforcement of the provisions of this chapter or the rules, regulations, or orders thereunder.

(c) Duty of mutual service companies to keep

Every mutual service company, and every affiliate of a mutual service company as to any transaction of such affiliate which is subject to any provision of this chapter or any rule, regulation, or order thereunder, shall make, keep, and preserve for such periods, such accounts, cost-accounting procedures, correspondence, memoranda, papers, books, and other records, as the Commission deems necessary or appropriate in the public interest or for the protection of investors or consumers or for the enforcement of the provisions of this chapter or the rules, regulations, or orders thereunder.

(d) Duty of persons engaged in service, sales, or construction to keep

Every person whose principal business is the performance of service, sales, or construction contracts for public-utility or holding companies shall make, keep, and preserve for such periods, such accounts, cost-accounting procedures, correspondence, memoranda, papers, books, and other records, relating to any transaction by such person which is subject to any provision of this chapter or any rule, regulation, or order thereunder, as the Commission deems necessary or appropriate in the public interest or for the protection of investors or consumers or for the enforcement of the provisions of this chapter or the rules and regulations thereunder.

(e) Use of forms other than prescribed by Commission unlawful

After the Commission has prescribed the form and manner of making and keeping accounts, cost-accounting procedures, correspondence, memoranda, papers, books, and other records to be kept by any person hereunder, it shall be unlawful for any such person to keep any accounts, cost-accounting procedures, correspondence, memoranda, papers, books, or other records other than those prescribed or such as may be approved by the Commission, or to keep his or its accounts, cost-accounting procedures, correspondence, memoranda, papers, books, or other records in any manner other than that prescribed or approved by the Commission.

(f) Examinations by Commission

All accounts, cost-accounting procedures, correspondence, memoranda, papers, books, and other records kept or required to be kept by persons subject to any provision of this section shall be subject at any time and from time to time to such reasonable periodic, special, and other examinations by the Commission, or any member or representative thereof, as the Commission may prescribe. The Commission, after notice and opportunity for hearing, may prescribe the account or accounts in which particular outlays, receipts, and other transactions shall be entered, charged, or credited and the manner in which such entry, charge, or credit shall be made, and may require an entry to be modified or supplemented so as properly to show the cost of any asset or any other cost.

(g) Submission by holding company or subsidiary to examination by holders of securities

It shall be the duty of every registered holding company and of every subsidiary company thereof and of every affiliate of a company insofar as such affiliate is subject to any provision of this chapter or any rule, regulation, or order thereunder, to submit the accounts, cost-accounting procedures, correspondence, memoranda, papers, books, and other records of such holding company, subsidiary company, or affiliate, as the case may be, to such examinations, in person or by duly appointed attorney, by the holder of any security of such holding company, subsidiary company, or affiliate, as the case may be, as the Commission deems necessary or appropriate in the public interest or for the protection of investors or consumers.

(h) Submission by mutual service companies and persons engaged in rendering service to examination by other companies

It shall be the duty of every mutual service company, and of every affiliate of a mutual service company, and of every person whose principal business is the performance of service, sales, or construction contracts for public-utility or holding companies, insofar as such affiliate or such person is subject to any provision of this chapter or any rule, regulation, or order thereunder, to submit the accounts, cost-accounting procedures, correspondence, memoranda, papers, books, and other records of such mutual service company, affiliate, or person to such examinations, in person or by duly appointed attorney, by member companies of such mutual service company and by public-utility or holding companies for which such person performs service, sales, or construction contracts as the Commission deems necessary or appropriate in the public interest or for the protection of investors or consumers.

(i) Uniform methods for keeping accounts; power of Commission to prescribe

The Commission, by such rules and regulations as it deems necessary or appropriate in the public interest or for the protection of investors or consumers may prescribe for persons subject to the provisions of subsections (a), (b), (c), or (d) of this section uniform methods for keeping accounts required under any provision of this section, including, among other things, the manner in which the cost of all assets, whenever determinable, shall be shown, the methods of classifying and segregating accounts, and the manner in which cost-accounting procedures shall be maintained