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129
CO - Contractual ObligationCoverage
Denial Code CO-129: Prior Processing Required
What Does Code 129 Mean?
Prior processing information is required from another payer before this claim can be adjudicated.
Group Code CO (Contractual Obligation): The provider has agreed to accept the payer's determination. The patient is generally not responsible for this amount.
Why Does This Happen?
This payer is secondary and needs the primary payer's EOB before processing.
How to Resolve It
- 1Submit the primary payer's EOB with the claim
- 2Verify coordination of benefits order
- 3Resubmit with all required prior processing documentation
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