How can I optimize deliverability as anti-spam solutions become the norm?

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Answer: Corporate anti-spam solutions developed by providers such as Postini, MessageLabs and Symantec have been implemented at many organizations, from small and midsize businesses to the largest Fortune 500 companies, to better protect their employees and infrastructure from the influx of spam. Understanding their latest approaches to fighting spam can help legitimate b-to-b marketers optimize their deliverability.

Over the past year, we have observed these companies rushing to introduce the earliest “reputation-based” anti-spam solutions into the corporate marketplace. Adoption of these solutions has been increasing because they can block large volumes of spam before it enters corporate networks, thus decreasing the server loads and other IT costs typically associated with traditional spam filtering techniques. In turn, a marketer’s e-mail sending reputation increasingly holds the key to b-to-b deliverability success.

While each anti-spam provider has its own way of assessing an e-mailer’s reputation, the basic concept is the same: Dozens of standard spam filtering tools, which may include traditional content filters, URL filters, header analysis, volume filters, spam traps and many other criteria, are incorporated into algorithms that produce a reputation score for an IP address similar to a credit score. An IP’s score then determines how much it gets filtered, which is a more effective approach to reducing both spam and false positives compared to legacy solutions that would subject all e-mail to the same amount of filtering regardless of the source.

The newest solutions are also meant to more effectively combat spam zombies (spam sent via hacked PCs) by identifying traffic pattern anomalies. For example, CipherTrust reports that about 30% of e-mail on any given day actually comes from IP addresses that have never previously been encountered, and the majority of them are sending spam.

In addition to following standard e-mail delivery best practices—which is absolutely critical—marketers should also follow these few extra steps to ensure a positive reputation and optimize their deliverability:

  • Send consistent volume from stable IPs. Sudden dramatic boosts in message volume can be perceived as a zombie attack, especially if originating from rarely used IPs or those that are typically used for low-volume messaging.
  • Conduct a domain count and contact enterprises directly. If you send a lot of e-mail to specific corporate domains, contact these companies and your contacts directly to request that they white list/safe list your IP address. Being on multiple corporate white lists is also sometimes used as a factor in reputation algorithms and can enhance your score across all a provider’s clients.
  • Authenticate your e-mail. Publish your SPF records and sign your e-mail with DomainKeys, as several providers have implemented authentication checking and are beginning to include authentication in their reputation scoring.
  • Continue to test your campaigns with content filters and monitor developments including the adoption of new anti-spam technologies at the companies you do business with.

Jordan Cohen is the director of ISP/government relations for Epsilon Interactive (, a provider of e-mail marketing solutions and marketing automation technologies.

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