Provider/Supplier Type(s) Impacted: Providers billing with specific MAMM Certification numbers

Reason Codes: Not Applicable

Claim Coding Impact: Mammography codes

Description of Issue: An issue was identified impacting mammography claims being denied with CARC 16, RARC MA128, MSN message 09.040 when the certification end date after 09/17/2029.

Noridian Action Required: Noridian is actively working with the MCS maintainer to resolve this issue.

06/08/26 - System updates were made and completed on 05/26/26. Mass adjustments are expected to be initiated by 06/12/26.

Provider/Supplier Action Required: No action required

Proposed Resolution/Solution: Not applicable

Date Reported: 5/18/26

Date Resolved: