Hi @BBenemelis there are a couple types of spam traps. Some were email addresses that were previously used by real people, but were deactivated due to inactivity. They are sometimes repurposed as spam traps to identify senders with poor database management practices. One way to identify them is finding records that had no activity and/or bounced continuously for a long time, then all of a sudden started accepting emails again. However, it's better to be proactive about removing inactive, unengaged records to avoid being "dinged" by sending to them once they've been converted to spam traps.
Another type of spam trap was never used by real people and was created solely as a spam trap. The way these might enter the database is through list purchases and otherwise questionable acquisition practices. (Please review your Marketo contract as there are terms relating to list purchases!) These usually have a greater impact, such as putting the sending IP on a block list such as Spamhaus. You often will get a notice from Marketo that you need to take immediate action, since this affects other Marketo customers' sending. You will need to try to identify and delete the record as part of the remediation process, and you may need to delete multiple possible records if it isn't clear which one is the spam trap.
The email deliverability power pack that was offered by Marketo (now Everest by Validity) provided some additional insights into which email campaigns sends hit spam traps, and that can help narrow down possible spam trap records.
.png)