it is spam if the e-mail address is not linked to an actual person, also if it does not have a pure subject. for instance a subject with lots of !!@@#!@3!#!@$#! or one that has all caps is generally considered spam. However, based on the Can Spam Act it is illegal for people to send spam. . however, since the addresses are not linked to a personal e-mail account noone can ever catch them. You can opt out of spam, but if you do you are likely to get more because they relaize that your address is active and will continue to send / try to sell / scandalize you.