Some of the network integrations that Swaarm supports can send blacklisted subIds on their API.
Swaarm can detect those subIds and automatically blacklist them for you.
In order to see this in action, you can follow the steps:
Go to the offer details page of the network that you want to check
Click on the Traffic Tab
In the reason column, you will find the text "network-sync". This stands for the subIds that the network sent via API
In order to check if the network sends traffic controlled (e.g. blacklisted) subIds in their API, go to its integration page here and find the table "Supported Fields", You can read there all the fields that are sent and integrated on Swaarm.