5 Things Marketers Should Know About Spam Filters

“It's harder to be relevant and interesting, but it pays off handsomely
in higher revenue,” says Stephanie Miller, vice president of market development at New York-based Return Path, an e-mail performance management company. She cites the example of a dating site that “significantly reduced complaints by offering choices on frequency and adding a bit of helpful advice to alerts that went to less active members.”

3. Marketers should check their spam credentials. For the most part, ISPs aren't going to tell marketers if their messages are getting tossed as spam because they don't want the "bad guys" to find out how they're judging the e-mails, say Buck and Smith.

When 95 percent or more of a marketer's e-mails are being delivered, that's good, Smith says. Senders should worry when that drops to around 70 percent or 80 percent, he says. E-mails in the latter percentage, even if there aren't any bounceback messages, may not be arriving in inboxes, he says.

ISPs dumping e-mails without telling senders is called "black holing," and it's more common than marketers think, says Jordan Cohen, senior director of industry relations for e-mail authenticating firm Goodmail Systems of Mountain View, Calif.

Buck, Cohen and Smith say marketers can review their ratings on sites like Spamhaus, which identifies spamming IPs; SpamAssassin, which has a program that rates e-mails according to how "spammy" they are; and through services like those of Return Path and Phoenix-based Pivotal Veracity, an e-mail delivery service provider.  

4. E-mail content should be designed with spam filters in mind, especially in the case of business-to-business copy, but still may be allowed to contain iffy keywords. Back to the XXX example, Buck says marketers should run their creative through spam filter tests before editing out questionable keywords. They may be able to stay, depending on the e-mail's context—including whether the sender is already in the recipient's address book, if the IP has a good reputation, if the sender is authenticating its e-mail and if it's certifying its e-mail through companies like Goodmail.

"That changes a little bit when you look at the B-to-B space," Smith says. "The filters being used at most corporations tend to be a little bit further behind in terms of advanced filtering systems ... you do need to be more concerned with content."

5. Allow time to warm up any new servers, which may be necessary when switching e-mail service providers. Cohen says volume triggers vary, depending upon domain, and they can be set off by mass mailings from new IPs. Often, ESPs take care of this need in-house, he says. But sometimes that doesn't happen. Cohen points to a client that didn't send out a few e-mails to establish its reputation on its new IP (the client had an excellent reputation on the old one) and got 20 percent of its mail blocked by AOL. "You need to have a pre-existing reputation in order to get delivered."

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