You can make any specific exclusion made with ClickGUARD permanent - which means ClickGUARD will never automatically remove it from your campaigns' exclusions lists.
You can do this:
for any specific exclusion record, in exclusion forensics
Manually blocking / excluding permanently
When manually blocking / excluding an entity, you always have the option to make the exclusion permanent:
Just check the box that says "Permanent" before applying the exclusion.
Making an exclusion permanent in forensics
At any time from exclusion forensics you can hit the "Change Duration" button:
You can then select "Permanent" and chose the campaigns for which you wish to make the exclusion permanent: