A third-party administrator shall maintain at its principal administrative office for the duration of the written agreement referred to in section 510.12 plus five years, adequate books and records of all transactions between it, insurers, and insured persons. The third-party administrator’s books and records shall be maintained in accordance with prudent standards of insurance recordkeeping. The commissioner shall have access to such books and records for the purpose of examination, audit, and inspection. Trade secrets contained in a third-party administrator’s books and records, including but not limited to the identity and addresses of policyholders and certificate holders, shall be confidential, except the commissioner may use trade secret information in any proceeding instituted against the third-party administrator. The insurer retains the right to continuing access to the third-party administrator’s books and records sufficient to permit the insurer to fulfill all of its contractual obligations to insured persons, subject to any restrictions in the written agreement between the insurer and third-party administrator on the proprietary rights of the parties in the third-party administrator’s books and records.