CMS Pub. 100-04, ch. 28, § 20.1

The term Medicare beneficiary identifier (Mbi) is a general term describing a beneficiary's Medicare

identification number. For purposes of this manual, Medicare beneficiary identifier references both the

Health Insurance Claim Number (HICN) and the Medicare Beneficiary Identifier (MBI) during the new

Medicare card transition period and after for certain business areas that will continue to use the HICN as part

of their processes.

Beneficiaries indicate that they have assigned their Medigap benefits to a participating physician/practitioner

or supplier by signing block #13 on the Form CMS-1500. This authorization is in addition to their

assignment of Medicare benefits as indicated by their signature in block #12.

Form CMS-1450 makes no provision for the provider to indicate that the beneficiary has assigned benefits

because the Form CMS-1450 is used only for institutional claims, for which payment is typically assigned to

the provider of services. For claims the institutional provider submits to A/B MACs (B) for physician

payments for physician employees; hospitals, SNFs, HHAs, OPTs, CORFs, or ESRD facilities may maintain

a beneficiary statement in file instead of submitting a separate statement with each claim. This authorization

must be insurer specific.

If the beneficiary has a Medigap policy, the following statement should be signed:

Beneficiary’s Medicare beneficiary

identifier

NAME OF BENEFICIARY MEDIGAP POLICY NUMBER

I request that payment of authorized Medigap benefits be made either to me or on my behalf to

_______________ for any services furnished me by that physician/provider/supplier. I authorize any holder

of medical information about me to release to (name of Medigap insurer) any information needed to

determine these benefits or the benefits payable for related services.

Since the beneficiary may selectively authorize Medigap assignments, caution providers about routinely

stamping item #13 of the Form CMS-1500 “signature on file.” The Medigap assignment on file in the

participating doctor/supplier’s office must be insurer specific. However, it may state that the authorization

applies to all occasions of services until it is revoked.

Effective with October 1, 2007, participating Part B physicians/practitioners and DMEPOS suppliers now

will only include the CMS-assigned Medigap claim-based COBA ID on an incoming claim if confirmation

that a beneficiary has authorized Medigap assignment has been obtained.