“Brian Thompson, CEO of UnitedHealthcare since 2021, was shot and killed outside an entrance to the New York Hilton Midtown in Manhattan, New York City, on December 4, 2024. He was in the city to attend an annual investors meeting for UnitedHealth Group, the parent company of UnitedHealthcare. Authorities believe the attack was not random. Thompson had been criticized for UnitedHealthcare’s rejection of insurance claims, and his family reported that he had received death threats in the past. The shooting occurred early in the morning, and the suspect, initially described as a white man wearing a mask, fled the scene.”

https://en.m.wikipedia.org/wiki/Killing_of_Brian_Thompson

(edit) I would like to point out that Luigi Mangione is only a suspect and there are currently doubts about the integrity of the evidence.