I've recently received spam from a registered New Zealand company sent via xtra/spark/yahoo mail servers from an xtra/spark IP address.
It was sent to a very specific email address which is listed on a club website and has clearly been scraped from a website.
I reported it to xtra/spark and got the following response..
Thank you for contacting Spark regarding the emails from this sender.
[myname], this is not considered Spam. This is a mail-out newsletter and gives you the option to unsubscribe which I suggest you do. Once the sender has updated their database you should stop receiving emails from this company.
Your CTS RightNow online reference for this case is [ref number]
In the middle of the spam message it says to unsubscribe please reply. Unsubscribe.
It's been drummed into people not to reply to spam as this is just a means to prove an email address is valid however telecom recommend this.
And how to telecom/spark get to decide if it's spam or not? It was unsolicited, I never opted in to the mailing list.