These docs are for v1.0. Click to read the latest docs for v2.0.

Mail Score is Activity which is performed to clean the Database and check its hygiene.
Netcore stores all the clients data in a central repository and maintains the logs for each email with the checks like Open, Click, etc in order to derive
Active: Activity done by a contact in last 6 months
Neutral: Contacts not in Netcore’s DB
In Active: No Activity done by a contact in last 6 months

Mail Score also checks for Spam Traps, Group ID’s, Foreign ID’s, Park Domains which is the primary reason for the Harvest Quarantine.