Lost in Translation? Common Misinterpretations of Email Marketing Best Practices

Recent conversations with both Senders and mailbox providers have led me to a realization: There is a large gap in how email marketers and mailbox providers interpret the meaning and application of BCP (Best Common Practices).

I attend a number of industry events to stay informed on where the industry is going, and make sure I’m up-do-date on the latest topics, technologies and ideas. The conversations I have with both mailbox providers and email marketers also ensures that I know how the two sides of the industry actually think about email in general. It was three such conversations that got me thinking about best practices and the potential for meaning and context to get “lost in translation” depending on which side of the industry you work on.

The first dialog with an industry insider was around list services, specifically how to build your list.  I completely understand why email marketers need to grow their lists. Fortunately, there are many methods for building an email list. Unfortunately, they’re not all good.  The specific topics at hand were list appending, email change of address and email validation. The question was, “What is the best way to do all three?”  I admit that I’ve often questioned whether there even is a right way.  There have been some pretty hard stances against these practices but I listened and took notes so I could follow up later.

The second telling conversation came from a client that was having issues sending to a particular mailbox provider and couldn’t understand why.  Talking through their practices they admitted that they grow their list mostly via co-reg.  Certainly co-registration is a way to build your list but it does come with some complications.  I wanted to push this further with the client but unfortunately the topic was considered off limits since it’s a legal practice and it has proven successful to this particular sender.  Note to self: Follow up later…

The third conversation was around how many IPs are needed to send out mailings in a timely fashion.  The sender was having a problem with a few mailbox providers that have very strict sending limits, i.e., they only allow so many mails per hour from a given IP address.  The sender said, “We need to get the mail out in a certain amount of time so we wanted to use approximately 300 IPs to get past the throttle limits.” They asked me if there would be any issues with this. From their perspective this practice was OK since it didn’t directly violate any rules.  My first response to them was, “you might look like a snowshoer.”  Their reply was, “No, because snow shoeing is on domains not IPs.”  Second note to self: Check that fact because it just doesn’t seem right.

Having these discussions and wanting to really understand the line for these practices I first referenced postmaster and anti-abuse sites.  Many mailbox providers and filtering companies have taken the time to describe, in detail, what they consider best practices so I started with Gmail – https://support.google.com/mail/answer/81126?hl=en

Reading through the bulk sender guidelines there were a few, specific sections that really stood out to me:


Gmail states, “Each user on your distribution list should opt to receive messages from you in one of the following ways (opt-in):

The key word here is “opt-in” which seems very straightforward. There are certainly different ways to opt-in, but Gmail helps by suggesting:

  • Through an email asking to subscribe to your list
  • By manually checking a box on a web form, or within a piece of software

With that in mind, let’s go back now to my conversation on list services and co-registration processes:  One would certainly opt-in for ECOA. Address owners have indicated they are changing their addresses and opted in to a service that will give marketers the correct address.  This practice shouldn’t be too much of an issue, right?  Removing any address that isn’t accurate, for example [email protected], is a good idea and I would consider a best practice.  That leaves list appending and co-registration and a big window of interpretation.

Many anti-spammers consider list appending to be an unacceptable practice since there is no direct permission, but there are no laws that say this is illegal. However, CASL could change that and require some proof of consent.  The simplest way to think of this is, did they come to you and say, “Hey, I want this”?  If not then you might find yourself having serious issues down the road.

Co-registration on the other hand does, in some fashion, ask for permission.  There is a check box stating that you would like to receive email from our partners, right?  The sender’s thinking is: “It’s checked so I guess that is an opt-in.” Except Gmail indicates that it should be “manually” checked, meaning the end user needs to actually take an action to indicate they want email.  In these co-registration situations the user gave permission, but they don’t know it’s you they gave it to, and this can result in issues which will come back to you as spam votes or a list full of unengaged users.  No worries, Gmail does recommend “that you verify each email address before subscribing them to your list.”  So it’s a best practice to confirm that address.  Don’t assume that all the information you are given is accurate, ask if it is.

Third Party Sender

Gmail doesn’t recommend this but if you do choose to use a 3rd party sender, then stay involved as much as possible and make sure you are identified correctly so those subscribers know exactly where and how they got your email.  Unfortunately you do have some responsibility to how these 3rd parties are representing you.  Their reputation can hurt yours.

Affiliate Marketing Programs

Affiliate marketing is a way to drive people to your site and ultimately to grow your mailing list.  However, these programs have long been associated to spammers and can cause delivery issues if not monitored closely.  It’s the responsibility of the email marketer to monitor the affiliates they use and to remove those that might be causing delivery issues.  Mailbox providers don’t always like this practice, since they see more issues and more negative feedback with these types of list growth.  So be warned if you do walk this path.


Now on to the last conversation I had about using roll-over IP addresses to avoid rate limits.  First, there might be a reason that some mailbox providers limit the amount of email allowed into their systems.  Some may not be able to handle a large amount of mail at a given time; others use this as a way to help fight spam coming into their systems.  Don’t misunderstand me. I don’t think that using several IP addresses to get mail out is a always bad thing, and I know that many email marketers do use this technique, but when you’re motivation is to bypass a filter then your mail might be considered snowshoe spam.  I refer to Spamhaus and their definition of Snowshoe spam and they state:

Like a snowshoe spreads the load of a traveler across a wide area of snow, snowshoe spamming is a technique used by spammers to spread spam output across many IPs and domains, in order to dilute reputation metrics and evade filters.”

To be clear, the sender I talked to is not a spammer and they do have a permission based list — in fact a COI list — so they’re sending to people that really want their mail. Despite this fact, the sender admitted that the reason they are spreading the mail across so many IP addresses is they want to “evade filters.” Mailbox providers watch behavior of senders as well. So while not all mailbox providers will bulk or block a sender using this practice, some might.

There are many ways to interpret and apply best practices, and if you look hard enough, you’ll find a justification for your needs. But be cautious! Review your data and question the total impact of your practices. The method you’re using to get into the inbox may be keeping you out.

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