Social network site Tagged was caught duping users into revealing the email addresses of their friends. Most people who used the social networking site signed up, then added the addresses of their friends as a way to keep in touch with them. The company found a way to get extensive email listings from users, by pretending to send emails to the friends of those users. The users were not aware that their listings were being used in this way, and Tagged was found out to have acted unprofessionally by abusing the users trust on this issue.