Introducing: appeal letter generation

Payers deny 20% of claims- $200B annually- and increasingly use AI to do it. Providers spend $20B fighting back manually, yet most denials go unchallenged. The ones that are? Often generic templates with mail-merged patient details. They get letters out the door, but leave money on the table.

We agree about one thing: appeals should follow a repeatable formula. But {name}, {address}, and {payer} aren't the variables that matter.

A winning appeal isn't a pro-forma, it's a legal argument. Evidence-based, yes, but persuasive within the constraints of the facts presented in the medical record.

What makes a good appeal letter?

Here are a few of the elements we always insist on an appeal letter including. This is most relevant in cases of denials due to a lack of medical necessity, but should have application elsewhere.

Policy compliance

This is the most important part of any appeal- and in our experience, the least well-handled.

To build a convincing case for overturn, you need to fully understand why the denial occurred. Sure, the CARC/RARC codes point you in the right direction, but for the forensic analysis your patient deserves, you need the actual medical coverage policy for their specific plan.

Now you're facing a 30-50 page quasi-legal document. Scan to the medical necessity criteria section. It's often split by clinical indication- make sure you're referencing the correct one. Medical necessity is structured as conditional AND/OR statements. Treat it as a logic decision tree.

Compare each criterion against the patient's medical record. Often there are multiple pathways that justify treatment. Be exhaustive in your mapping. Even if the payer rejects your first clinical indication, they'll be forced to overturn based on the others you've documented.

Of course, the payer will do their own mapping between documentation and policy. But doing the work yourself- presenting a succinct, cogent analysis in your appeal letter- makes overturn far more likely, and faster.

It's the difference between a public defender passionately arguing their case in the courtroom versus neatly presenting evidence in a bound dossier for the judge to review at their leisure.

Clinical evidence

If policy compliance is known to be important but done poorly, clinical evidence is typically ignored altogether.

This step means searching relevant clinical studies and- the gold standard- published guidelines from professional medical bodies to support why a treatment was recommended.

It's much harder for a payer to deny a claim for lack of medical necessity when the national professional body they recognize has published guidance that the treatment is strongly recommended.

Good sources: PubMed for peer-reviewed studies, Google Scholar for clinical literature, specialty society guidelines for gold-standard recommendations.

Case law

Citing relevant legal precedent is another tool in your arsenal. Use it sparingly- it won't apply to every denial. But many cases are surprisingly applicable to everyday claims.

For example: In Ryan S. v. UnitedHealth Group, Inc. (9th Cir. 2024), the 9th Circuit held that applying more restrictive utilization reviews to behavioral health claims than to medical or surgical claims violates parity. Parity is established in the MHPAEA Final Rules (2024). This applies to a huge volume of mental health and substance use denials.

Kennedy v. Braidwood Mgmt., Inc. (2025) resulted in the Supreme Court upholding the Affordable Care Act's preventive-services mandate. Insurers must cover USPSTF "A" and "B" rated services. This can be highly relevant for preventive care denials (contraceptives, cancer screening, vaccinations).

When a denial potentially violates federal or state law, saying so tips the balance in your favour.

Previous appeals

Sometimes the best argument is simple: you've denied similar cases before, and they were overturned at Independent Medical Review by state regulators.

Perhaps it's in everyone's interest to resolve this now, before escalation.

Making this argument requires two things: (a) access to a large dataset of previous appeals, and (b) the ability to analyze it and surface semantically similar claims.

How Penelope handles appeals

Your teams face an impossible choice: use templates and sacrifice overturn rates, or manually craft strong letters and burn valuable hours.

Penelope combines the speed of templates with the success rates of personalized appeals.

1. Upload the medical note with plan and payer details

2. Penelope retrieves the plan-specific policy for the recommended treatment

3. Clinical history is mapped against medical necessity criteria to build an airtight case

4. Relevant clinical guidelines are pulled from professional bodies

5. Applicable case law is incorporated automatically

6. Semantically similar previous appeals against this payer surface for reference

7. A comprehensive appeal letter generates in minutes, not hours

Built by a physician who spent his residency fighting for patients to get the care they deserve, through increasingly creative means.

If you'd like to find out more, reach out to our founders or book in for a call:

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