30 U.S.C. § 1713
A lessee, operator, or other person directly involved in developing, producing, transporting, purchasing, or selling oil or gas subject to this chapter through the point of first sale or the point of royalty computation, whichever is later, shall establish and maintain any records, make any reports, and provide any information that the Secretary may, by rule, reasonably require for the purposes of implementing this chapter or determining compliance with rules or orders under this chapter. Upon the request of any officer or employee duly designated by the Secretary or any State or Indian tribe conducting an audit or investigation pursuant to this chapter, the appropriate records, reports, or information which may be required by this section shall be made available for inspection and duplication by such officer or employee, State, or Indian tribe.
Records required by the Secretary with respect to oil and gas leases from Federal or Indian lands or the Outer Continental Shelf shall be maintained for 6 years after the records are generated unless the Secretary notifies the record holder that he has initiated an audit or investigation involving such records and that such records must be maintained for a longer period. In any case when an audit or investigation is underway, records shall be maintained until the Secretary releases the record holder of the obligation to maintain such records.
30 U.S.C. § 1713