Frequently misunderstood and feared, blacklists vex many email marketers. To those without the benefit of experience, blacklists seem liable to penalize any sender on a whim, but industry veterans know that's not the real story. The savviest understand where the hazards are and how to avoid them.
Misconceptions
There are many common misconceptions about the way blacklists operate. Frustrated senders find them to be secretive with no discernible rules, begging the question, how do you fix something you don't understand? Some accuse blacklist operators of holding an anti-marketing agenda, intentionally disrupting commercial email.
Part of the secrecy claim is true: because many rely on spam traps — mailboxes monitored for sending violations — and spam traps' addresses need to be secret to be effective, marketers can't know which names on their lists trigger blacklisting events. However, blacklist operators do strive to apply consistent rules, including remaining blind to message context. Their goal isn't to flag marketing; it's to flag unwanted email. In reality, they base blacklisting decisions on three factors: spam traps, complaint rates and malicious links.
Senders that understand the landscape take these six steps to stay off blacklists, or to quickly remediate blacklisting events:
1. Track and apply engagement metrics. Use your engagement data to identify inactive subscribers, and either re-engage them or stop sending to them. Make sure your systems are correctly processing unsubscribe requests and feedback loops to remove people who don't want your email.
2. Isolate your unengaged segment. Send campaigns to segments with weak engagement from a distinct sending IP — not your main IP. If you have a spam trap on your list, this will make it easier to isolate while preventing it from threatening your primary IP's inbox placement rates.
3. Tightly control list composition. The best way to do this is to compile your own lists. Buying lists may seem like an easy way to gain new subscribers, but the risks of spam traps and complaints usually outweigh the benefits. Furthermore, make sure you know where your new subscribers are coming from. Were these new email addresses from an online purchase, or a more error-prone point-of-sale collection?
4. Use only dedicated IPs. When you share a sending IP with other senders, you have no control over how they use it. However, you'll certainly pay if they abuse it. Blacklist operators aren't able to distinguish your sending practices from others, so if their messages trigger a blacklisting, your baby will be thrown out with their bath water.
5. Be aware of timing. Know and take fewer risks during periods of increased blacklisting. Return Path research identified concentrations of blacklisting events on Wednesdays and Fridays. Sundays and Mondays saw fewer events. November and December (holiday season) represented 49 percent of blacklisting events in 2013.
6. Know who to call. Reputable senders do sometimes find themselves blacklisted, and the operators listed here provide guidance to address these events:
- Spamhaus: SBL, XBL, PBL*
- Spam Cop
- psbl.surriel.com
- cbl.abuseat.org
- URIBL
- SURBL
- ubl.unsubscore.com.
(* Spamhaus states this technically is not a blacklist.)
Tom Sather is the senior director of research at Return Path, an email marketing solution that helps to improve deliverability and ROI.
- Companies:
- Return Path, Inc.