17 C.F.R. § 242.1007
If records required to be filed or kept by an SCI entity under Regulation SCI are prepared or maintained by a service bureau or other recordkeeping service on behalf of the SCI entity, the SCI entity shall ensure that the records are available for review by the Commission and its representatives by submitting a written undertaking, in a form acceptable to the Commission, by such service bureau or other recordkeeping service, signed by a duly authorized person at such service bureau or other recordkeeping service. Such a written undertaking shall include an agreement by the service bureau to permit the Commission and its representatives to examine such records at any time or from time to time during business hours, and to promptly furnish to the Commission and its representatives true, correct, and current electronic files in a form acceptable to the Commission or its representatives or hard copies of any or all or any part of such records, upon request, periodically, or continuously and, in any case, within the same time periods as would apply to the SCI entity for such records. The preparation or maintenance of records by a service bureau or other recordkeeping service shall not relieve an SCI entity from its obligation to prepare, maintain, and provide the Commission and its representatives access to such records.
17 C.F.R. §242.1007