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As per CMS, Box 12 - The patient or authorized representative must sign and enter either a 6-digit date (MM | DD | YY), 8-digit date (MM | DD | CCYY), or an alpha-numeric date (e.g., January 1, 1998) unless the signature is on file. In lieu of signing the claim, the patient may sign a statement to be retained in the provider, physician, or supplier file in accordance with Chapter 1, “General Billing Requirements.” If the patient is physically or mentally unable to sign, a representative specified in Chapter 1, "General Billing Requirements” may sign on the patient's behalf. In this event, the statement's signature line must indicate the patient's name followed by “by” the representative's name, address, relationship to the patient, and the reason the patient cannot sign. The authorization is effective indefinitely unless the patient or the patient's representative revokes this arrangement.
NOTE: This can be "Signature on File" and/or a computer generated signature. The patient's signature authorizes release of medical information necessary to process the claim. It also authorizes payment of benefits to the provider of service or supplier when the provider of service or supplier accepts assignment on the claim.
Signature by Mark (X) - When an illiterate or physically handicapped enrollee signs by mark, a witness must enter his/her name and address next to the mark.
BOX 13 - The patient’s signature or the statement “signature on file” in this item authorizes payment of medical benefits to the physician or supplier. The patient or his/her authorized representative signs this item or the signature must be on file separately with the provider as an authorization. However, note that when payment under the Act can only be made on an assignment-related basis or when payment is for services furnished by a participating physician or supplier, a patient’s signature or a “signature on file” is not required for Medicare payment to be made directly to the physician or supplier.
The presence of or lack of a signature or “signature on file” in this field will be indicated as such to any downstream Coordination of Benefits trading partners (supplemental insurers) with whom CMS has a payer-to-payer coordination of benefits relationship.
Medicare has no control over how supplemental claims are processed, so it is important that providers accurately address this field as it may affect supplemental payments to providers and/or their patients.
In addition, the signature in this item authorizes payment of mandated Medigap benefits to the participating physician or supplier if required Medigap information is included in box 9 and its subdivisions. The patient or his/her authorized representative signs this item or the signature must be on file as a separate Medigap authorization. The Medigap assignment on file in the participating provider of service/supplier's office must be insurer specific. It may state that the authorization applies to all occasions of service until it is revoked.
NOTE: This can be "Signature on File" signature and/or a computer generated signature.
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