D.C. Mun. Regs. tit. 27, r. 27-4740
The Director may, at reasonable times and places, audit the books and records of any person who has submitted data to substantiate offered prices pursuant to section 4741 of these rules to the extent that the books and records relate to that data. A person who receives a contract, change order, or contract modification for which the data is required, shall maintain books and records that relate to the cost or pricing data for three (3) years from the date of final payment under the contract, unless a shorter period is otherwise authorized in writing.
The Inspector General, District of Columbia Auditor, or Director shall be entitled to audit the books and records of a contractor or any subcontractor under any negotiated contract or subcontract, other than a firm fixed-price contract, to the extent that the books and records relate to the performance of the contract or subcontract. Books and records shall be maintained by the contractor for a period of three (3) years from the date of final payment under the prime contract and by the subcontractor for a period of three (3) years from the date of final payment under the subcontract, unless a shorter period is otherwise authorized in writing.
The Inspector General, District of Columbia Auditor, or Director may, at reasonable times, inspect the part of the place of business of a contractor or any subcontractor which is related to the performance of any contract awarded or to be awarded by the District.
D.C. Mun. Regs. tit. 27, r. 27-4740