I didn't get the email, but I think it wants YOU to put that email address on YOUR safe sender list in your email options (on yahoo or gmail or aol or outlook or wherever you manage your mail).
Basically what that does is allow emails originating from that address to go directly into your Inbox, not straight to your Spam folder.
As they'll probably be sending out the email to hundreds (if not thousands) of recipients, your ISP has no way of knowing if it's SPAM or not.
By putting them on your safe sender list (or whatever your email system calls it), it just tells the ISP that you know it's okay to receive it in your Inbox.
Or not (as I haven't seen the email). :wink: :wink: