Debunking the Myth of 3rd Party Email Certification

By Inboxable

Marketers frequently ask our analysts the same question: Does third-party email certification actually work?

The real, and much more meaningful, question brands should be asking is: “Do I need third-party certification to get my messages to the inbox?” The resounding short answer is “NO”. 

It is the Internet Service and Mailbox Providers (ISPs) job to ensure that their users get ONLY the emails they want. To achieve this goal top ISPs are looking at the types of emails their users open and interact with. This is what we call gauging user engagement. How this process works is the more subscribers that open an email the better the sender’s reputation is. As a marketer’s sending reputation improves, so does the number of emails it is able to successfully deliver to the inbox and the amount of time it takes for delivery.

Essentially, a positive reputation results in the ability to bypass ISP filtering mechanisms, preserve message images, and lesser punishment of abuse complaints, hard bounces, and mailing to non-engaged users.

Both certified and non-certified emails have to go through the same validation process in order to land into the inbox of their intended recipients. This process in determined by each individual ISP and entails a number of thresholds for metrics such as abuse complaints, hard bounces, spam trap hits, etc. With certified emails specifically, exceeding one of these thresholds could do a two-fold damage:

  • Remove the certification of sending IP(s)
  • Negatively impact sending reputation which can lead to bulking or blocking of a marketer’s messages

Staying within each ISP’s acceptable thresholds by following best practices like sending only to active users, as well as maintaining a consistent volume and mailing frequency will yield the same great results for both certified and non-certified senders. Maintaining a healthy email program is truly the only requirement for achieving the best inboxing rates possible.

The Experiment

Our Deliverability team set out to evaluate the extent to which 3rd party email certification played a part in achieving optimal inboxing rates. To do so, our experts selected handful of non-certified senders from different industries and helped them follow industry best practices on audience segmentation as well as mailing volume and frequency. The goal was simply to ensure that senders abide by the mailing rules outlined by each major ISP and maintain a positive sending reputation. The team provided guidance on campaign deployment across major mailing days like Black Friday, calendar holidays like Christmas or Thanksgiving, acquisition and reactivation efforts, and much more.

The primary ISPs that were considered for this experiment were Yahoo, Microsoft, Comcast, and Road Runner-both Comcast and Road Runner combine Cloudmark’s anti-spam services with their own reputation management scores. We compared each marketer’s inboxing and open rates with their respective industry averages over a period of six months and this is what we discovered:

The inboxing rates of our marketer set were achieved without 3rd party certification of their sending IPs. By keeping their mailing lists clean and following best practices non-certified marketers were able to achieve and maintain above-average inboxing rates and increase mailing list size and frequency without penalties and negative impact on inboxing rates.

The Bottom Line

Whether your sending IPs are certified or not, how emails perform at each ISP ultimately determines if a brand’s message will land in the inbox or the spam folder. As long as your subscribers remain active and your mailing lists-clean, your program can achieve all of the benefits of email certification, without any of the costs!



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