Colo. Rev. Stat. § 24-106-106
The state shall be entitled to audit the books and records of any contractor or subcontractor under any negotiated contract or subcontract to the extent that the books and records relate to the performance of a state contract or subcontract, if the state is able, in conducting any such audit, to maintain the confidentiality of any information contained in the books and records that is deemed proprietary as determined by the state. Such books and records shall be maintained by the contractor for a period of six years after the date of final payment under the prime contract and by the subcontractor for a period of six years after the date of final payment under the subcontract, unless a shorter period is otherwise authorized in writing.
C.R.S. § 24-106-106
This section is similar to former § 24-103-601 as it existed prior to 2017.