[tyingq]

Cool. I know Microsoft has an email address classifier they use for things like product beta signups. See these examples:

https://flow.microsoft.com/providers/Internal.User/users/joe...

https://flow.microsoft.com/providers/Internal.User/users/joe...

It classifies things like gmail, yahoo mail, hotmail as "Consumer" addresses.

So, there might be some additional markets for you if you can identify "consumer" emails vs "business". Also, some niche areas like isEduEmail(), for things like student discounts (fyi, not as simple as it seems at first glance).

[GordonS]

Interestingly, if you try an @yandex.com address you get back a true "isViral" property. Wonder what that means?

[tyingq]

Don't know, but you get "isViral" for zoho.com, amazon.com, google.com, tencent.com, pinterest.com, and others as well.