42 C.F.R. § 489.72
In the event a Surety has paid CMS on the basis of liability incurred under a bond obtained by an HHA under this subpart F, and to the extent the HHA that obtained such bond (or the Surety under § 489.71 ) is subsequently successful in appealing the determination that was the basis of the unpaid claim or unpaid civil money penalty or assessment that caused the Surety to pay CMS under the bond, CMS will refund to the Surety the amount the Surety paid to CMS to the extent such amount relates to the matter that was successfully appealed by the HHA (or by the Surety), provided all review, including judicial review, has been completed on such matter. Any additional amounts owing as a result of the appeal will be paid to the HHA.
42 C.F.R. §489.72