Sep 28, 2006

Case study: Innocent email marketer gets accused of spam, blacklisted

Recently, we had a long time user on MailChimp get blacklisted for spamming. As soon as we received notification from the blacklist organization, we investigated the account. Something was wrong…

We took a look at their account information, and things just didn’t add up. They looked like the perfect email marketer:

  • For one, the customer has been with us since 2002, with no prior abuse complaints whatsoever.
  • They’re a large, well-known University
  • They’d been sending email campaigns very regularly to their Alumni list
  • Their bounce rate was usually well below 10%
  • Their unsubscribe rate was always close to zero
  • Their open rate was usually between 40%-50%
  • They never had any abuse complaints before (not even from an accidental pressing of the "junk" button)
  • Their list growth over time was slow and steady. Totally organic growth.
  • Nothing was really different about their email design. For the most part, they followed the same format they always did.

So what gives?

To be safe, we suspended the user’s account and left them a voicemail. They responded instantly (always a good sign that they care). They were confused about what was going on too. After much discussion with several people in their department, we figured out the cause.

Every semester, the university gets a new batch of graduating students. When they graduate, they can opt-in to receive the alumni email newsletter.

When the university adds each new batch to their email newsletter list, they actually send them a reminder message. Something like, "Just a reminder that when you graduated, you opted-in to receive the alumni newsletter. You should be receiving your first issue in about one month."

This is a very effective way to prevent false spam reports, by the way. Which confused us even more. How could someone so responsible get reported as a spammer?

Well, the person in charge of email marketing was away on maternity leave. So her  temporary replacement, not knowing about the "reminder" emails, just added the new batch of graduates to their master list and sent away (and technically and legally, there’s nothing wrong with that, because these students opted in!).

A couple graduates forgot how they got on that email list, and reported it as spam.

All it took was a couple complaints (out of a list of 30,000+ recipients) to get blacklisted.

Some of you might be wondering: "Since they sent it via MailChimp, wouldn’t that mean that MailChimp got blacklisted, and not the university?" Before you assume that using a 3rd party email service protects your company from getting blacklisted, you should know that spam filters have learned to scan for URLs inside of messages they’ve flagged as spam. If your URL gets on the list, they’ll delete all future emails that just contain your URL (such as an innocent little link to your website!), no matter where it was sent from. Some of them referred to the blocked URLs as "spamvertisers." Scary, huh?

Luckily, the university responded super fast, and we were able to send an explanation to the blacklist admins about what happened. They were delisted within hours. The user did nothing wrong. If anything, they go above and beyond making sure their list is totally permission based. This just goes to show how quickly people forget opting in to lists, and how important it is to remind people how you got their emails.

See also: Preventing Spam Complaints

and: Sending your 1st campaign to an old list?