Final answer:
Entering SIGNATURE ON FILE in Block 12 of the CMS-1500 claim means that the patient has signed a Consent for Release of Information form, giving their consent for the healthcare provider to share their medical information with the payer for payment and reimbursement purposes.
Step-by-step explanation:
Entering SIGNATURE ON FILE in Block 12 of the CMS-1500 claim means that the patient has signed a Consent for Release of Information form. This form allows the healthcare provider to release medical information to the payer, such as an insurance company or government program. By signing the form, the patient gives their consent for the healthcare provider to share their medical information with the payer for purposes of payment and reimbursement.