Spam Complaints Matter

When you're fighting spam, you reach out to a lot of different people. If you received spam and you're savvy enough, you send it to the ISP from whence it originated, and ask them to take action to make the spam stop. If you work for an ESP or a blacklist group, you might reach out to the sender and ask them to prove that this person opted-in, with details, in order to resolve the "he said, she said" situation inherent to most spam complaints.