Ask the Experts: Cloudmark Q&A

Recently, I hosted a webinar in our Ask the Experts series; the subject of this one was Cloudmark. It was a packed 30 minutes of content and great questions, but unfortunately, I didn’t have time to answer all of them! So, as promised, here are the questions I couldn’t get to that will hopefully shed more light on Cloudmark!

Is there a complaint threshold that Cloudmark utilizes?
While we do not know the exact complaint threshold that Cloudmark uses for their filtering, Cloudmark and Return Path have agreed upon a threshold to enforce for compliance in Return Path’s Certification program. If a Certified sender’s 30-day average complaint rate exceeds 1.0% at Cloudmark, the sender’s IP will be temporarily suspended from the program. This means that the IP will not receive preferential treatment at the Cloudmark network until its complaint rate drops below 1.0%.

We have never had a problem with spammy Cloudmark fingerprints in the past. Why are we all of a sudden being hit with Cloudmark issues?
There are a few factors that could be contributing to a seemingly “random” Cloudmark issue. Ask yourself the following questions:

  • Have you changed your email templates or refreshed the content of your campaigns recently?
  • Have you sent to any lapsed subscribers lately? In other words, an audience that hasn’t opened/clicked or received any emails from you in several months?
  • Have your complaint rates at the mailbox providers that use Cloudmark risen recently?

If the answers to any of the above are “yes,” you may want to focus on that part of your email program. Changing content, sending to potential spam traps, and increased complaint rates can all contribute to spammy Cloudmark fingerprints.

So if we sent an email to our seed list, but not to any of our actual subscribers, we can assume that the spammy fingerprint is due to content?
Most likely, yes. The main drivers of spammy fingerprints are spam traps, complaints, and content. Since the Return Path seed list will not complain about your mail (as the seeds do not interact with any messages), and because the seeds are not spam traps, you can rule out those factors.

Are images considered content if they are not secure source links? I was wondering if secure versus non-secure image path links make a difference here.
Images are generally considered content whether the links are secure or non-secure. Some mailbox providers have started treating emails with non-secure images poorly, so it’s a good idea to use secure source links when possible.

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