Overview
UCEPROTECT Level 3 is the most aggressive tier β when too many subnets under an ASN (Autonomous System Number) get listed in Level 2, the entire ASN's IP space gets listed. Large cloud providers and ISPs can have their entire IP ranges flagged.
Due to its enormous scope, most mail administrators don't use Level 3 for actual blocking β it's treated more as reference data.
How It Works
The system counts Level 2 listings per ASN. When the count exceeds the threshold, the entire ASN gets listed in Level 3. Given that large operators may own millions of IPs, this granularity is highly controversial.
How to Get Delisted
Like Level 2, Level 3 clears automatically when underlying listings decrease. As an end user, there's not much you can do β this requires your ISP or cloud provider to improve the spam situation across their entire IP space.
This blacklist does not support manual removal. Listings expire automatically once the underlying issue is resolved.