Incident 591: Cigna Algorithm PXDX Allegedly Rejected Thousands of Patient Claims En Masse in Breach of California Law

Description: Cigna health insurer faces a class-action lawsuit for allegedly using the PXDX ("procedure-to-diagnosis") algorithm to automatically reject over 300,000 patient claims in violation of California law, prompting two members to file the lawsuit seeking damages and a jury trial. Cigna disputes the allegations, claiming the process expedites physician reimbursement and does not result in care denials.


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Alleged: Cigna developed and deployed an AI system, which harmed patients.

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Daniel Atherton
Cigna Sued Over Algorithm Allegedly Used To Deny Coverage To Hundreds Of Thousands Of Patients · 2023

Cigna, the healthcare and insurance giant, was hit with a lawsuit on Monday that alleges the company systematically rejects claims in a matter of seconds, thanks to an algorithmic system put in place to help automate the process—further rai…

Cigna Health Giant Accused of Improperly Rejecting Thousands of Patient Claims Using an Algorithm · 2023

SACRAMENTO, Calif. (AP) — A federal lawsuit alleges that health insurance giant Cigna used a computer algorithm to automatically reject hundreds of thousands of patient claims without examining them individually as required by California la…


A "variant" is an incident that shares the same causative factors, produces similar harms, and involves the same intelligent systems as a known AI incident. Rather than index variants as entirely separate incidents, we list variations of incidents under the first similar incident submitted to the database. Unlike other submission types to the incident database, variants are not required to have reporting in evidence external to the Incident Database. Learn more from the research paper.