UnitedHealth's care-denial algorithm loses 9 out of every 10 appeals. The lawsuit says the company kept running it anyway, because it knew only 2 in 1,000 patients would ever file one. Run that math. If 0.2% of denials get appealed and 90% of those get reversed, a denial that's wrong nine times out of ten still sticks more than 99.8% of the time. The tool is called nH Predict. UnitedHealth bought its maker, naviHealth, in 2020. Case managers feed in a patient's age, living situation, and…