Even though Brian Thompson led one of the biggest health insurers in the U.S., he was largely unknown to the millions of people affected by his decision-making. Wednesday's fatal shooting of the United Healthcare CEO on a midtown Manhattan sidewalk — which police call a targeted killing — thrust the executive and his business into the spotlight.

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.