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CO-59 - Denial Journal
CARC CO — Contractual Obligation

CO-59

Processed based on multiple or concurrent procedure rules

What This Code Means

Payment was reduced because multiple procedures, multiple surgeries, or concurrent anesthesia rules applied.

Common Causes

  • Multiple surgical procedures performed in the same session
  • Concurrent anesthesia billed without required modifiers

How to Resolve or Appeal

  1. Confirm standard multiple-procedure payment reduction rules apply correctly
  2. Verify modifiers (51, 59, etc.) were applied where appropriate

Educational reference only — not medical or legal advice. Always confirm code usage and appeal rights with the specific payer.

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