[opyate]

Nice, with pushdata, do you check if someone uses the same GMail account using GMail's "plus" and "dots" [0] features? (E.g. given [e-mail], then [e-mail], [e-mail], [e-mail], [e-mail] etc are all valid and points to the same address.)

0. https://gmail.googleblog.com/2008/03/2-hidden-ways-to-get-mo...

[rlonn]

Nope, there is no restriction for plus addresses. I validate email addresses and specifically allow + and . in the part before the @ sign. [e-mail] and [e-mail] will be considered two different users.

Have to add also that the "plus feature" isn't a Gmail-specific invention but a standardized way of referring to the same mailbox using different addresses. But some email providers don't support this feature, and many input validators out on the Internet don't either.