One marketer has discovered that he had to think beyond best practice email marketing or suffer a negative impact on search rankings.

It seems email marketing's impact on post-Panda search rankings can affect brands that believe they are upholding best practices. As one business' experience proves, even if subscribers have opted to receive messages, marketers should consider whether they are active readers to avoid a drop in rankings.

On a Web Developer forum, LockerGnome.com, Jake Ludington explains that his email marketing campaigns have always been a priority. Ludington requires a two-click subscription, offers easy unsubscibe options and automatically removes people from the mailing list when they mark a message as spam. When his site rankings dropped dramatically, he was surprised when someone at Google gave him a tip that his domain was being penalized for email behavior.

Although Ludington ensures that the people receiving his marketing newsletters have opted in, he realized that he wasn't keeping tabs on how many of them were active readers. He tells other marketers facing email-related drops in search rankings, “These inactive subscribers are the ones you need to worry about.”

Inactive subscribers damage email reputation, and now, Ludington asserts that Google uses Gmail data in a way that inactivity damages search reputation. The takeaway for marketers is that they need to remove “subscription deadwood” from their email lists. Because this audience isn't engaging email content, it isn't convertible, anyway.

Of course, marketers may also want to work to fight against “subscription deadwood” by offering continuously fresh email content that will catch clicks. As Brafton has reported, an email marketing study showed that fresh content can be used to re-engage old leads, with one business not only boosting email open rates but reconverting 40 old leads within a few weeks.

Katherine Griwert is Brafton's Marketing Director. She's practiced content marketing, SEO and social marketing for over five years, and her enthusiasm for new media has even deeper roots. Katherine holds a degree in American Studies from Boston College, and her writing is featured in a number of web publications.