Spam Traps: I Want to Play a Game

List Hygiene will always be a part of our day-to-day life as email marketers. There will always be best practices to implement, there is always testing to be done, and we will always want to avoid certain types of email addresses.

But why avoid any type of email address? Isn’t it our goal to acquire and send to as many subscribers as possible? One of the biggest misconceptions is that any recipient list will work. However, to maintain a good reputation and improve your deliverability, you should only be sending to people who want and expect your email. Unengaged recipients (those who don’t open or click messages) should be dropped from your list and you should always be aware how your server processes bounces. Not maintaining your mailing list can lead to complaints, low read rates, high unknown user rates, low subscriber engagement, blacklisting, a drop in IP address reputation and eventually in deliverability.

Amongst many other ‘side effects’ of not following list hygiene best practices, there is one type of email addresses many marketers sometimes are not even aware of: Spam traps. Do you know if you have spam traps in your mailing list? How many of the email addresses in your list are actually spam traps? Want to find out?

First Get to Know Your ‘Enemy’
A spam trap is an email address or server specifically designed, maintained, and monitored to catch abusive email traffic and identify poor data practices. Spam traps are used by mailbox providers across the globe to ensure senders are following email best practices. Mailbox providers use spam traps to help determine your sending reputation. Keeping spam traps to a minimum is important for the overall health of your email program.

While spam traps may be thought of as a mechanism for capturing spam emails, a M3AAWG paper on best practices for creating and operating spam traps defines a spam trap as “a honeypot used to capture any kind of email abuse.” This could be spam, phishing, malware, or other abusive bot activity, however, any marketer not following list hygiene best practices might end up having spam traps on their list. 

There are two types of spam traps you need to be aware of:

  • Pristine spam traps, have never been used as a legitimate email address and have been set up by mailbox providers and security companies with the sole purpose of capturing bad senders. These addresses could end up on your mailing list if you engage in email address harvesting and other illegal practices or if you buy or rent your lists from untrustworthy sources. If you have a pristine spam trap on your lists it will immediately indicate to mailbox providers that you are an untrustworthy sender.
  • Recycled spam traps, sometimes called re-purposed spam traps, are addresses that were at one time legitimate destination addresses obtained with permission that were abandoned by the original user and have since been repurposed to catch abusive email. These addresses can also trap legitimate marketers with weak data-quality practices and make them look like spammers.

The Battlefield
Some of the most common reasons spam traps are on your mailing list:

  • Inactive subscribers have been turned into recycled spam traps by mailbox providers.
  • You have poor list hygiene or are receiving addresses from partners with poor list hygiene.
  • You are purchasing email addresses from a list broker.
  • You are harvesting addresses or receiving addresses from partners who practice list harvesting.
  • You have a security breach in your network and a spammer has gained control of your list file.

Let’s Fight!
To avoid spam traps, senders should first of all follow best practices, which include:

  • Sending your email only to consenting subscribers and permission-based lists.
  • Maintaining good list hygiene by emailing your list regularly and monitoring the age and activity of your email addresses.
  • Moving old, disengaged subscribers (e.g. any subscriber who has not opened your messages in the past six months) to a different list and try to re-engage them.
  • Keeping a sound email infrastructure and maintaining secure systems and databases.

Your Weapons and How to Use Them:

  • When you are thinking or enlarging your mailing list try to avoid purchasing, renting, or leasing email addresses from third-parties. If you do enlist a third party, make sure that they are not using list harvesting techniques. In such cases you are never aware of whether or not the email addresses were being collected properly, making it very possible that you are buying in fact spam traps.
  • Reject subscription requests from malformed addresses, such as [email protected] Username typos can happen when email addresses are collected offline and later have to be entered into a database. Website registration and shopping cart forms are also attracting more and more fake emails, which might just happen to be a spam trap address. Also reject subscription requests from role accounts such as: [email protected] [email protected], [email protected] and [email protected]
  • Use a confirmed opt-in or double opt-in permission method for all new subscribers to make sure that an email address belongs to a real person. By requiring subscribers to verify their address, you can ensure your list is never contaminated with an invalid address that, at best, will bounce, and in the worst case scenario is a spam trap.
  • Use CAPTCHA during the subscription process to help prevent list poisoning. A validation tool on your enrollment page will also catch typos and non-existing email addresses before they make it to your mailing list.
  • Have a process for:
    • Handling hard and soft bounces and removing unknown users immediately. Also, paying attention to your bounce notifications and removing invalid email addresses will help you prevent hitting spam traps.
    • Re-engaging and/or removing old and inactive subscribers. Holding on to chronically inactive addresses for too long are like an unhealthy relationship: they aren’t of any value to your email program and some of the addresses are at risk of being converted into spam traps.

Your Advantage with Return Path
It’s a fight half won if you know your enemy, right? Since spam traps look like regular email addresses, it’s hard to spot them in your mailing list. Use the Return path Platform to your advantage to see if you are hitting Spam Traps and even differentiate between pristine and recycled traps. High unknown user rates and blacklisting’s can also be a good indicator, all of which you can check and monitor with the Return Path Platform. Be ahead of the game!

Also, senders certified through Return Path’s Certification Program have insight into the detailed complaint, unknown user, and spam trap data from multiple sources around the globe. Senders can use this data to identify spam trap hits and work to remove them from subscriber lists.

What You are at Risk of Losing
Depending on the type of spam trap you hit, how many times this spam traps is hit, and how the spam trap provider handles the hits at their end your sender reputation could be potentially damaged, causing bounce rates to increase and your deliverability (the percentage of emails delivered to the inbox of your subscribers) to decrease leading eventually to a decrease in ROI.

Your IP addresses may be added to a blacklist providers database, which means your deliverability will be affected. One of the main reasons for getting blacklisted is sending email to spam traps. Our reputation and Sender Score solution ensures you understand the key metrics that drive reputation and mailbox provider filtering decisions. We monitor the most important blacklists in the industry and alert you in our platform if any of your IP addresses are compromised by a blacklist hit.

If you hit a spam trap operated by one of the major mailbox providers, such as Yahoo or AOL, they could permanently blacklist your sending domain and if you hit a trap operated by an anti-spam organization (for example, Spamhaus or SpamCop) delivery of your emails to all mailbox providers—as well as companies who consult their databases—will be affected because they use that information to filter incoming email.

Play Smart!

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