Blocklist Removal Center
Mailing Lists -vs- Spam Lists
Associated Documents

The Definition of "Spam"
Email Marketing FAQs
Doing a Permission Pass
Solicited Bulk Email is an important mechanism for keeping consenting customers informed of products or service news. When Bulk Email is Solicited it is valuable to the recipient and therefore also to the sender. When it's Unsolicited it's purely Spam, an unwanted and unwelcome nuisance to the recipient, unfairly forcing the recipient to assume the cost of receiving, storing and removing the unwanted adverts.

The difference between senders of legitimate bulk email and spammers couldn't be clearer, the legitimate bulk email sender has verifiable permission from the recipients before sending, the spammer does not.


All bulk email sent to recipients who have not expressly registered permission for their addresses to be placed on the specific mailing list, and which requires recipients to "opt-out" to stop further unsolicited bulk mailings, is by definition Unsolicited Bulk Email, a/k/a "Spam".

Unconfirmed Opt-In

If an Opt-in request is unconfirmed, then it can not be verifiied. If it can not be verified then the Bulk Email Sender can simply say "You opted-in" which is why all spam claims "You opted-in to this list".

According only to the Bulk Email Sender, the Recipient has somehow, unverifiably, initiated a request for an address to be subscribed to the Bulk Email Sender's mailing list. The Bulk Email Sender has subscribed the address to a mailing list without verifying if the address owner has in fact granted permission or not.

In the vast majority of cases the Bulk Email Sender has simply harvested the address from the Internet or purchased the address from another spammer and "opted it in" himself.

Unconfirmed Opt-in means that anyone can subscribe any address regardless of whose it is, therefore anyone can subscribe "" and according to the list owner, the President has 'opted-in'.

Unconfirmed Opt-in is an excuse for spammers to harvest or buy lists and simply claim "Opt-in" where there was none and is why Unconfirmed Opt-in lists are known as "dirty lists" in the respectable bulk email industry and "Block the sender on sight" lists in the anti-spam industry.

In the event of a "spam" accusation:

The Bulk Email Sender has no verifiable proof that the recipient consented to be placed on the bulk mailing list and is therefore liable for having sent Unsolicited Bulk Email a/k/a Spam. Action can be taken against the Sender. The sending of Unsolicited Bulk Email is against all ISP Terms of Service worldwide, is illegal in many countries, and is against Spamhaus SBL policy.
Legitimate Bulk Email

Closed-Loop Opt-In

Known as "Confirmed Opt-in" or "COI" in the legitimate bulk email industry, also known as "Verified Opt-in" or sometimes "Double Opt-in".

With Closed-Loop Opt-in the Recipient has verifiably confirmed permission for their address to be included on the specific mailing list, by confirming (responding to) the list subscription request verification. This is the standard Best Practice for all responsible Internet mailing firms.

COI ensures users are properly subscribed, from a working address, and with the address owner's consent.

In the event of a "spam" accusation:

The Bulk Email sender is fully and legally protected because the address owner's reply to the Subscription Confirmation Request received back from the address owner proves that the address owner did in fact opt-in and grant verifiable consent for the mailings.

This simple protection means that the Bulk Email sender can not be legitimately listed on any 'spam' blocklist, or legitimately terminated for spam complaints by an ISP since he has an actual email from the address owner confirming the subscription.

"COI: a way to turn a horribly performing bloated list that demands a specialist ESP to mail and manage, into a high-performing list that a small business with a one-man IT department could handle." - Bill Cole
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