"[OIG] reviewed 20 of 62 contracts that [CMS] identified as awarded for the development, implementation, and operation of the Federal marketplace to determine the contract requirements for monitoring and overseeing contractor performance. Contracting officers and contracting officer's representatives did not always manage and oversee contractor performance as required by Federal requirements and contract terms. CMS did not always comply with Federal regulations regarding designation and certification requirements for contracting officer's representatives. Also, contracting records did not always include all critical contract deliverables and other management and oversight documentation."