Brian Thompson led one of the biggest health insurers in the US but he was largely unknown to the millions his decisions affected

United Healthcare CEO Brian Thompson is dead after being the target of a fatal shooting in New York City Dec. 4. He was 50.

Calling the incident a “brazen targeted attack,” police said the suspect was waiting for Thompson before shooting him outside of a hotel in Midtown Manhatten. But while authorities stressed that the killing was “premeditated” and planned, the motive for the shooting is still unknown.