Ever heard the word "spam trap" floating around the email marketing world? People call them different names, but any email address that exists to try and catch spammers in the act falls under this category. ISPs like Yahoo! and Gmail use spam traps to lure mass email marketers with sketchy list tactics. They may post the phony spam-trap email address on a website somewhere to see if it starts to get email. Those email addresses aren't real people, so they never sign up for any email. Therefore, anyone who sends to that email address has been caught "harvesting" email addresses, which is illegal and a quick way to get taken to court.
Opt-in email marketing – also called permission-based email marketing — pros won't ever get caught by these so-called pure spamtraps. Most legitimate email marketers don't have to fear this type of trap, in fact, unless they purchase email marketing lists, where you don't know the original collection tactic or source.
In addition to pure spamtraps, ISPs may recycle old, inactive email addresses for recycled spamtraps. This one hits valid email marketers a little harder. If a subscriber signed up to receive your emails 5 years ago and then stopped using that email address, you may still have them on your list when that address gets opened back up as a spam trap. This is a huge reason why it's important to clean out hard bounces immediately and to consider trimming inactive contacts from your list over time.
Want more information on spamtraps? Briteverify does a great job diving deeply into the topic on their blog in the article "The Truth About Spamtraps."
Read more posts from the emfluence team about email marketing deliverability.