There was a book that came out in 2010 titled Delay, Deny, Defend: Why Insurance Companies Don’t Pay Claims and What You Can Do About It. It’s an analysis of the insurance industry (not just healthcare, but with a special focus on healthcare) that details how insurance companies operate to delay approvals of insurance claims, deny insurance claims, and defend wrongful denials in court. It basically shows how it is cheaper for insurance companies to not pay lawful claims and fight them in court than to pay out claims.

When Luigi Mangione killed the UHC CEO last year, he left behind 3 bullet shells at the scene of the murder with the words “Delay”, “Deny” and “Depose” written on the bullet shells. It was a pretty clear reference to the book, and was the first indication (before Mangione was caught) as to the motive of the shooting.