Email Addresses That You Never Want to Email

In my last blog post, I wrote about the best practices in email deliverability that marketing and sales technology vendors should follow. In doing so, I noted how some vendors include a focus on email validation. In this post, I am focusing on email validations that every B2B organization should perform – and that every marketing and sales technology vendor should automate by default.

Known competitor domains 

Sending competitors marketing and sales emails not only gives away competitive intelligence, but also increases the spam reports your organizations will receive, as competitors are likely to report your emails as spam. To help with this issue, many organizations create a list of all competitor email domains (e.g. @ACME.com) and use it to create an exclusion rule. We recommend not doing so through form validation as competitors will simply enter their personal email addresses. Rather, create a filter in the marketing/sales application that flags or otherwise excludes these contacts. More rigorous companies go a step further by determining their competitors’ IP addresses and then excluding contacts that have previously accessed their Web site, landing pages or emails through one of those IP addresses. Are these practices by 100 percent effective? No, but doing so dramatically decreases the number of competitors you will email.

Role-based email addresses

Role-based email addresses go to distribution lists that go to more than one person. When numerous people receive these email addresses, it’s not likely that every person on the distribution list gave permission to receive your email. As a result, these emails tend to produce a large number of spam complaints. For this reason, I recommend excluding marketing emails to role-based email addresses. Include validation rules to your online registration pages and filters that prevent the distribution of emails to role-based email addresses. Below find a list of email addresses that you can add to validation and filters:

Mailing lists

Mailing lists allow users to create their own email distribution lists and function similarly to role-based email addresses. Validate against them in online registration pages and also filter them out when sending out marketing emails. Listed below are some of the most popular mailing lists, but because many mailing lists allow custom branding of a mailing list,  this will not exclude 100 percent of mailing lists. However, it will significantly decrease the number to which you send email:

Malformed email addresses

Many times, email addresses are incorrectly specified due to typing errors  (e.g. Jay@gmail.xcom rather than Jay@gmail.com). For the most frequently entered email address domains, create validations that catch these errors. For example, if a person’s email address contains “gmail.com” it must also contain “@gmail.com,” validating that the email address’s  “back end” is correctly specified.

Spam detection and blacklist services

There are several spam detection and blacklist services that identify email and IP addresses that send unsolicited email messages. Don’t send marketing messages to these organizations, as common sense dictates that it increases the potential of ending up on one of the lists which they manage.

Note: I’ve listed some of the most popular spam detection and blacklist services below. I recommend using wild cards (as reflected below) so as to catch their delineations. Keep in mind that these organizations also maintain spam traps that don’t include their domain in the email, so though this will help, it won’t steer you 100 percent away from missteps with spam detection services.

Wireless device domains

Though typically not a significant issue for marketers, there are domains that, when found within an email address, mean that the messages go to wireless devices such as cell phones and pagers. These domains (full list maintained by the FCC) should never be sent unsolicited marketing email.

Though putting these steps in place will help improve your email deliverability practices, it does not factor into account where you source marketing contacts and the relevancy of your messages. Simply focusing on email address validation in isolation from focusing on how you contact acquisition and messaging strategy is akin to putting $16,500 rims on a beat-up 1972 Ford Pinto – the rims look great, but the overall impact to the car is negligible.