Medicare Claims Processing Manual (Pub. 100-04), Ch. 23 § 20.9.5
Adjustments
20.9.5 - Adjustments
(Rev. 1, 10-01-03)
A/B MACs (B) adjust for underpayment if the wrong, lower paying code is paid on the first of multiple
claims submitted. If the wrong, higher paying code is paid on the first of multiple claims submitted, A/B
MACs (B) pay the subsequent claim(s) and initiate recovery action on the previously paid claim(s).