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Defining Unsolicited Bulk E-mail

Ugh...yeah, we all feel the same way. Such an amazing waste of human attention and compute energy this topic causes.

What is UBE?

Before we begin, let us clarify that the terms “Junk” and “Spam” are used interchangeably by most e-mail users at the time of this writing. It could be argued that Spam is technically Unsolicited Bulk E-mail (UBE), and Junk is just “undesired e-mail” which is usually unknowingly solicited and also usually bulk (SBE – Solicited Bulk E-mail), but that appears to only add to the confusion. E-mail terminology debates aside, let us assume for purposes of this document that we are talking about the same thing when we call e-mail “Junk” or “Spam”, plainly: unwanted e-mail.

Furthering clarification of terms, let us clarify a new term: “Unsolicited Bulk E-mail” or UBE, which is what mail providers constantly battle against. While “Junk” and “Spam” are better looked at as subjective terms depending on personal viewing preferences. UBE is a term for automated e-mails being sent by bad actor parties in bulk with no intent to follow e-mail compliancy rules. These e-mails barrage large quantities of users with scammy content in a hope to grift a few cents from ads, or your entire life savings if they get lucky enough.

Effectively, UBE is postage-due mail, meaning the sender has very little cost associated with sending (especially because they typically send through unaware 3rd parties that have been hijacked via trojan or other malware), while the recipient server and recipient e-mail address pays the price upon receipt. That price is typically in the form of wasted time by the recipient users, as well as wasted storage space, processing, electricity, and data transit by the provider. More simply, sending UBE is theft of resources.

It should go without saying that here at Mindpack Studios we have a zero tolerance policy for any users sending UBE, and KYNGIN goes to great lengths to eliminate any UBE.

Over the last 20 years of hosting e-mail, we have had hundreds of conversations with customers which have mentioned how much “Junk” e-mail they receive. From the mail users perspective, it’s quite honestly “Junk” or “Spam”. These are e-mails which they received and they didn’t want, and by that simple explanation, it’s “Junk E-mail”. From the mail hosting companies perspective (our perspective), this is typically all e-mail the user signed up for in some way, which isn’t officially “UBE” by definition, and unfortunately isn’t something we can put a stop to using spam prevention system, because quite simply, it’s not “spam”. (This isn't entirely true, our systems learn, so using the Junk folder to teach the systems about e-mail that you consider 'junk' does work. To maximize resources, we'd recommend training the systems with only legitimate spam e-mail though, any subjective junk that has an unsubcribe link, please use where possible.)

All that said, lets quickly clarify. UBE’s definition is in the name, and must match all 3 criteria to be confirmed UBE: Unsolicited, Bulk, and E-mail:


Content that you never requested to have. This is important, because many times end users receive e-mail because it is solicited. And sure, solicitation may not have been exactly honestly acquired, many times it’s an automated signup or small printed “I agree” checkbox which is selected by default when you were checking out at a digital store or kiosk. We also can agree that this e-mail is probably still “unwanted” when you receive it, and probably also something we’d all likely classify as “Junk E-mail”. BUT, it’s absolutely not “unsolicited”. And that means from our perspective (the mail service provider) it’s not provided by a bad actor and not UBE.

So a quick recap to drive the point home: If you ever gave your e-mail to a commercial establishment, you probably signed your e-mail up to an “agreement” in which allows the establishment to send you advertisement e-mails in the future. When you get e-mail from a legitimate physical store (hardware store, home decorating store, etc) under these circumstances, you can be certain this is NOT UBE. You may believe it’s ‘Junk’ or ‘Spam’, and you can call it that, and you’d be accurate because to you it is junk. But it’s not UBE. This “agreement” you (unintentionally or not) signed, immediately disqualifies this e-mail as UBE (or “Junk E-mail” when seen from the mail providers perspective).


This second part is also important. People, even if they send you an advertisement, can’t be considered a bulk sender unless they are sending quantities of e-mail in an automated form. When a person sends e-mails directly to you individually without the aid of a bulk sending tool, even if they contain advertisements, the e-mail is not UBE, it’s just correspondence. Another quick recap: Automated e-mail is e-mail sent from a computer program that targets (usually) large quantities of recipients. Many times this is completed with a virus or malware by an unaware computer or server, or with specific software created for the purposes of sending large amounts of e-mail unattended. E-mail – (Obvious enough) These are messages you receive via e-mail service provider and through your e-mail client. The other definition is for “Junk E-mail”, which quite simply is just mail you don’t want.


E-mail recipients call all kinds of e-mail “Junk”, and quite truthfully to its name, it’s “just junk” to them. But this type of junk e-mail is not officially UBE, and for that reason it’s not officially designated as Spam by our servers. We are driving this point home because it will become very important in understanding this article, which you should read next if you can spare the 5 minutes as it clears up a vast majority of the deliverability trouble we experience hosting e-mail, and you likely will experience when sending it.

Learn more details on what KYNGIN does to defend against UBE.