COI

Double opt-in (also called “confirmed opt-in”) can help to prevent list hygiene problems, but some people are dead set against it. I’m not going to change their minds. I’m not even going to try to. But I’ve seen some changes at Gmail lately that lead me to think that I’m doing the world a disservice if I don’t at least warn you: If you’re a small newsletter publisher or small marketing sender, if you’re anyone using an SMB-focused or shared resource focused email sending platform, you’re putting yourself at risk by not employing double opt-in.Recently, a number of us in the email deliverability space started to hear that a bunch of smaller email senders, ones that were otherwise doing just fine yesterday, were suddenly finding their mail going to the spam folder in Gmail mailboxes today. Diving into it, this was all specific to a certain email provider, and was

Oracle’s Chad S. White recently shared four fantastic tips on how to maximize your response rate when implementing a double opt-in (aka confirmed opt-in) process. It’s a great way to verify consent (and keep a clean email list), but one of the primary complaints from marketers has always been the low response rate; the percentage of people who will complete the opt-in step is often far less than one hundred. COI/DOI may not be right for every situation (and indeed I just recommend to a client that they consider eliminating a similar process in their site registration because of the challenges they were facing), but it’s still a very good thing to consider in a lot of scenarios. Anyway, enough of my natter, click through to read Chad’s thoughts on the topic.

What is COI/DOI? It’s just address validation and permission verification — you send a welcome or verification message and the recipient has to click on a link to prove they want the subscription. And it’s not a new thing, here’s me talking about it on this very blog fifteen years ago.I consider the terms “double opt-in” and “confirmed opt-in” are interchangeable. I find that most of the time, internet security and anti-spam folks call it COI, and marketers and some deliverability folks (like me!) call it DOI. When doing so, they refer to the same process of requiring an active response to the initial welcome or verification email.There are a lot of good reasons to implement COI/DOI, but today’s specific question is — does Germany “require” it? Ultimately this is a legal question, and I’m not a lawyer, so I’m not qualified to answer legal questions. So this is not legal…

Verifying email addresses through methods akin to what we now think of as confirmed opt-in (COI) or (DOI) isn’t a new thing. Mailing list software Majordomo added support for verifying new signups way back in 1996. I don’t remember exactly when it became common to validate that opt-in via an email click, but I remember building email click tracking — sending out a unique indicator per subscriber and taking action or updating a status — for my own purposes way back in late 1997 as part of a spam filtering system I had built at the time. Then in 1998 I started a COI/DOI email list for my friend’s jazz club using custom code (not captured by the Internet Archive until 2001). So, it’s been done before.

Kickbox interviewed a bunch of us to find out what methods of opt-in we recommend. Go check it out. What’s your favourite method of opt-in?