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What is an Email Blacklist?

Rob Schneider
What is an Email Blacklist?

What is an email Blacklist? Or is it a Blocklist?

Are they the same? Did I leave the oven on?

Ok, settle down. And I’m not sure about the oven thing, unless there’s cookies involved to which we should investigate ASAP!

Back to the cookies… wait, I mean email blacklists. Sometimes we take for granted the weird things we deliverability people know versus what our clients know. Given the fact that our clients come from a variety of backgrounds and experience levels, it’s always good to take a step back and make sure we’re all on the same page and not tossing out concepts you aren’t familiar with. This is why we want you to understand what blacklists are and how they relate to both your email deliverability and overall email marketing performance.

Recently, I’ve had a few clients inquire about email blacklists, what they are and what’s the big deal about them. I spoke a little bit about these blacklists in the Spam Trap article but didn’t reference the term blacklist at all (not even once! Shame on me!). So while much of the content may be similar and intertwined, I’ll try to add a little bit more depth here to give you some further context and how spam traps and blacklists are related.

What’s an Email Blacklist? If your first thought is of a blacklist is being shunned, you’re right. Just in the email sense. Fortunately, it is possible to get unshunned, but unfortunately, it’s also possible to be reshunned. So how does all this shunning business work? Let’s discuss the fun of the shun.

The terms blacklist and blocklist are fairly interchangeable. And if you use either one, we’re going to know what you’re talking about and not even bat an eye at which one you used. Not even under our breath, I mean, well… probably not. Often times, both are abbreviated BL for short, as in RBL which can stand for Reputation or Real-time Blacklist/Blocklist.

Blacklists are usually the end result of hitting spam traps from spam trap networks. There are other multiple types of blacklists, but the most common one’s clients run into are the spam trap versions. As we previously discussed, there are millions of spam traps out there and several spam trap networks. One of the things these spam trap networks do is “publish” their findings as listings. These listings make up the “blacklist” or “blocklist”. Depending on the spam trap network, these listings could be private or they could be public.

Shunning Once you’ve been listed, consider yourself shunned. You’ve been slapped with silence. It’s now possible for the whole world to see how bad you are. Doesn’t it feel good to be noticed? Yeah, I didn’t think so. At this point, many mailbox providers, ISP’s and corporate systems usually reference some sort of blacklisting service as a part of their email filtering process. The tricky part is not everyone references the same lists and they won’t disclose who uses what.

This is where the deliverability impact can be catastrophic to almost non-existent. You see, if you made it on to a small obscure blacklist that no one is referencing, chances are that you aren’t going to see a shift in your metrics. However, hit a list that everyone references, and your whole company will be knocking at your door! Isn’t nice to feel wanted? Yeah, still not so much.

Unshun So what’s next? How do you get unshunned?

Just like we talked about in the spam trap article. Retrace your steps backwards and figure out what data source triggered the listing and undo it. Make sure that doesn’t happen again and once you’ve done that, you can reach out to the blacklist provider and explain what went wrong and how you fixed it and then nervously await their decision. If they require more information, send it. The more helpful you can be, the more helpful they will be.

If all goes well, you will be unshunned and removed from the blacklisting, also known as being delisted and your deliverability should improve automatically. Exhale your sigh of relief and make a note to not do that again. If you do, you know what happens… Reshun!

Reshun Regardless of which blacklist you made it on to, realize that even if it’s a low impact one, it still points to potential issues with your data and or data sources. If you don’t identify the reason or source, that little listing can creep up to a bigger one and it only gets more difficult to clean up. In addition to the fact that the backlist provider may be less likely to delist you repeatedly since you obviously didn’t do an adequate job the first time. In this case, they may impose a waiting period of like 30 days before you can request another delist, so it’s important to make sure you do it right the first time.

No Fun in the Shun
That’s the gist of email blacklists and how they work in conjunction with spam trap networks. While not all of them operate this way, a large number do. Getting listed is never fun but is often a learning experience that you can pass along to upper management on why email marketing best practices matter and the cost of not abiding by them.

P.S. – Any word on the oven? Pretty sure I smell chocolate chip cookies…

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