Cigna's PxDx algorithm auto-denied 300,000 health claims in two months, spending 1.2 seconds per case with no physician review

Cigna deployed an automated system called PxDx (procedure-to-diagnosis) that bulk-denied health insurance claims as "medically unnecessary" without any physician actually reviewing individual patient files. ProPublica's investigation revealed that a single Cigna doctor could deny up to 60,000 claims per month by rubber-stamping algorithm outputs in batches of 50 at a time, taking about 10 seconds per batch. Why it matters: Patients with legitimate medical needs receive automatic denial letters, so they must navigate a complex appeals process that most lack the knowledge or energy to pursue, so treatable conditions go untreated or worsen during weeks-long appeal windows, so emergency room visits and hospitalizations spike as conditions deteriorate, so the healthcare system absorbs far higher costs than the original denied procedure would have incurred. The structural root cause is that ERISA (the Employee Retirement Income Security Act) governs most employer-sponsored health plans and limits remedies to the value of the denied benefit itself, meaning insurers face no punitive damages for wrongful denials. This creates a rational economic incentive to deny claims algorithmically at scale, knowing that the small percentage of patients who successfully appeal will only recover what was owed in the first place, while the vast majority of wrongful denials generate pure profit.