Marketers Guide to Email Reputation Threats


A clean list is just one part of creating a successful email marketing program, but it is one of the most important parts. The advantages of doing periodic hygiene and verification on your email database can help you reduce the malicious and low-quality addresses on your list, provide a more accurate diagnostic and business metrics, improve your inbox delivery, and decrease the risk of being blocklisted.

Understanding what types of emails are in your database and the actual risks of using them can allow marketers to evaluate and determine which are best to send for their business. Webbula categorizes email threats into four buckets;  reputation, fraud, delivery and conversion. In this article, we will be discussing what makes up reputation threats and how to protect yourself.

According to Webbula’s 2021 Email Hygiene and Verification Trends and Benchmarks Report, “We saw reputation threats as a percentage of all threats identified spike in 4Q 2020. We expect to see similar levels in 2021 as email marketers continue to be aggressive about growing their databases during the COVID-19 pandemic.”


So what are email reputation threats, how do they end up on a list, and how can you tell if they’re on yours right now?

1. What are email reputation threats?

  • Blocklisted Emails are addresses used to identify spam.
  • Spam Traps are created and monitored by blocklist firms and anti-spam organizations and are intended to catch malicious senders. Spam traps look like real email addresses, but they do not actually belong to someone.
  • Honeypots are email addresses specifically created and placed in various areas online to collect information about IP addresses, used to help combat email fraud and spam. They are deliberately hidden in websites, code, and forms to be picked up by harvesters, bots, and malicious actors.
  • Moles are people behind email addresses that report campaign statistics to real-time blacklists. It works in much the same way as a mole used by the police to catch criminals. Organizations enlist and empower average people to rat out spammers.
  • Seeded Trackers are addresses used in marketing campaigns to track delivery rates. While they aren’t technically harmful, they are there because someone is tracking your activity.

2. How do email reputation threats end up on your list?

  • Reputation threats such as honeypots, and spam traps can impact you even if your list is 100% double opt-in(DOI).

Let’s say an email address opted-in and confirmed their interest (that’s DOI) years ago. Then at some point they stopped opening and clicking on your email messages. If the owner abandoned the email address, the ISP may have turned it into a honeypot. Sending to the address could end up damaging your sender reputation.

Purchased lists

We see this a lot in our industry and I wouldn’t say it's always the marketers fault. Many times, it's leadership that recommends purchasing a list and with little to no idea about how it could harm the business. In their eyes, it's a “shortcut” to try and build their database and drive sales. However, doing so can actually make matters worse for your marketing program for a few reasons:

  1. These addresses did not opt-in to receive messages from you. You could be violating laws such as CASL, GDPR, & CCPA.
  2. They could cause you to be labeled as a spammer.
  3. Your deliverability & sender reputation could be damaged.
  4. Your IP address and/or domain might end up on a blocklist.
  5. All this could negatively impact your ability to meet your marketing goals.

Purchasing lists can be a quick fix, but how do you know if the people behind the emails want your product? Or better yet, how do you know if there really are people behind those emails? You could be purchasing a list full of spam traps, bots, disposable domains, phishing emails, seeded trackers, moles, and more.

Good email lists are never for sale and most ESPs won’t let you email to a non-opt-in list to protect their sender reputation. It takes time to grow a good email list.

  • Not cleaning your list regularly with email hygiene

Marketers set up a one-and-done verification of their emails, but they ignore the importance of maintaining a clean mailing list. Just because you have an email verification service does not mean that your list is full of  perfect subscribers.

Emails are abandoned overtime and then turned into honeypots or spam traps. If that is the case, verification will tell you if those collected emails are valid or invalid, but sometimes those emails used to sign up for your content, webinar or newsletter could look like a valid email, but end up being a bot, spam trap, honeypot or more. Mailing to these emails can put your ip on a blocklists.

3. How can email reputation threats cause harm?

  • Poor Deliverability

Deliverability rate is the percentage of email that reaches the subscribers’ inboxes. If your message fails to make it to the inbox, if it lands in the spam folder, junk mail, or is blocked by the ISP instead, then your deliverability rate will take a hit. Sending to honeypots, spam traps, moles or seeded trackers won’t get you to the inbox. This will hurt your deliverability rate.

  • Damaged Sender Reputation

Your sender reputation measures how often you send, how many emails you send, the bounces that occur, and spam traps that are hit, among other factors. These results are tied to your IP and/or domain. If you’re sending to a list that hasn’t been cleaned, you’re putting your sender reputation at risk and could potentially find yourself on a blocklist.

  • Blocklisted

Blocklists are created to prevent email from being sent to inboxes that have not opted-in to receive an email. Many email marketers will eventually find themselves on at least one domain or IP blocklist at some point in their career whether they are good or bad senders, which is why it’s crucial to use email hygiene to avoid it.

The impact of having your domain or IP on a blocklist can cause huge disruptions and negatively impact your ability to send.

While no single preventative measure will guarantee zero blocklisings, if you are doing everything in your power to send an email that people want (not purchasing lists), and clean your list regularly, it will make the process of getting delisted much easier.

4. Regularly clean your list to avoid sender reputation, performance, and delivery issues

  • Catch the harmful threats at the front door: Validate email addresses at the point of capture with triple layer protection. (reCaptcha, DOI, real-time email verification)

Consider implementing ReCAPTCHA and adding double opt-in to your forms. Using double opt-in is a great solution because once a customer signs up for your emails, they will receive a confirmation link to continue the sign-up process. This is made to make sure that real people are signing up for your emails and not bots.

Another way to protect yourself is by implementing a cleansing service that coordinates with your CRM, email service provider, or lead capture forms to ensure the best top-of-the-funnel-data quality leads are entering your list.

A real-time cleaning API is designed to quickly determine if the email being submitted is a valid working email address and not a bot. This will help decrease the fraudulent or inaccurate data submitting into your forms, protect your deliverability and sender reputation, and improve campaign ROI. On the front end, it will create a better experience for your customers.

  • Remove them at the back door: Email Hygiene and verification are needed to identify these harmful threats

Some in the email industry recommend removing all unresponsive email addresses like this from your list - but that could mean losing 30% or more of your subscriber base. That’s overkill. It also overlooks the ‘billboard’ effect of email, where just reading your subject line motivates people to visit your website or one of your brick-and-mortar locations.

Regular list hygiene and verification can remove known honeypots and other threats from your list while not dramatically correlating the size of your database.  You’ll be able to analyze better and segment before you hit send and risk hurting your sender reputation.

Keep your email list squeaky clean, maximize deliverability, and minimize business-halting threats. Download Webbula’s 2021 Email Hygiene and Verification Benchmarks report now.