The EXCLUDE direct input field allows you to enter person-, group- or certifier names so as to exclude certain user(groups):
Examples:
Jane Boss/ACME
VIPGroup 999
*/Management/ACME
In case multiple Actions are to exclude the same users, you can either use (a) corresponding group(s) from the public addressbook, or create so called Access Definitions in the MC Configuration database for further re-use across multiple Actions.
NOTE: When checking EXCLUDE without selecting any Access Definitions and without supplying any direct input, all users who have the role [Admin] in the MC Configuration database will be excluded from the respective Action.