The Hidden Rule Makers Behind Prior Auth and Claim Denials: How InterQual, MCG, HealthEdge, Zelis, Lyric, and Optum’s CES Write the Criteria Payers Use to Reject Care and Why That’s Where Real Reform

Key Takeaways

• InterQual holds ~60% of prior‑auth market; MCG ~30%.
• Optum’s CES, Lyric, HealthEdge, Zelis control claim‑editing engines.
• Vendors often earn 15‑30% of “savings,” incentivizing denials.
• Same corporate parent may own both rule engine and payer.
• AI overlays now generate millions of sub‑second denials.

Pulse Analysis

The prior‑authorization ecosystem has become an oligopoly, with InterQual and MCG supplying clinical criteria to the majority of commercial, Medicaid and Medicare Advantage plans. Their combined market share—about 90%—means that virtually every denial or request for additional documentation traces back to a rule set created by these vendors rather than the payer itself. This concentration simplifies integration for health plans but also concentrates power in a few proprietary algorithms that are largely invisible to clinicians and patients.

Financial incentives further skew the system. A significant portion of payment‑integrity vendors operate on a contingency model, pocketing 15‑30% of the projected savings they claim to generate. This creates a perverse incentive to flag more services as unnecessary, inflating denial volumes. Compounding the conflict, companies like Optum own both the rule‑authoring tools (InterQual, CES) and the payer platforms that apply them, blurring the line between objective clinical judgment and profit‑driven automation. The infusion of AI and large‑language‑model overlays now enables sub‑second, high‑volume denials, amplifying the impact of these incentives.

Regulatory efforts such as CMS‑0057‑F focus on data exchange standards and reporting timelines but stop short of addressing the criteria layer or the contingency fee structures that drive denials. For reform to be effective, policymakers must look upstream to the vendors that craft the rules, enforce transparency around algorithmic criteria, and consider prohibiting contingency‑based pricing in payment‑integrity services. Only by dismantling the hidden rule‑making monopoly can the industry reduce unnecessary barriers to care and restore trust among providers and patients.