The Medicare share of the cost of covered services furnished to Medicare enrollees by providers that are owned or operated by the HMO or CMP or are related to the HMO or CMP by common ownership or control must be determined in accordance with the apportionment methods set forth in part 412, §§ 413.24 , 413.55 , and 415.55 of this chapter.
42 C.F.R. §417.554