answer:You could easily set up a filter in most email clients that I’m familiar with (Yahoo mail, Gmail, Hotmail and Outlook, to name a few) that will filter out mail from a specific individual or even an entire domain and drop it into your spam folder. That doesn’t involve giving anything to anyone else, since you completely control the filter (and spam folder) on your own client system. That may have been the advice that was given to you to “flag the email”; it’s done on your system, not theirs. No one else would have your email address, in that case.