Allegrow's API and application will provide statuses as a result of email verification for each email address you provide to us.
Here's a short summary of how you can consider each status:
'safe' = valid (safe to send to / provide customers, both catch-alls and non-catch-alls included)
'block_bounce_risk' = invalid
'dead_email' = invalid (often won't bounce even though it's incorrect, typically due to a server catch-all set-up)
'do_not_mail_abuse' = valid (with higher spam report risk)
'unknown' = inconclusive (re-run after 30 days)
'spamtrap' = valid (but high spam trap risk)
'more_time_required' = (*sync endpoint only* more checks are still being run). Either retry later or upgrade to the asynchronous API to avoid this.
'missing_email' = invalid (there's likely a syntax error on the email, making it invalid or not correctly structured as an email).
You can find further guidance on how we suggest using each status in your GTM process or application here.