Spam reporting

Spam reporting, more properly called abuse reporting, is the activity of pinning abusive messages and report them to some kind of authority so that they can be dealt with. Reported messages can be email messages, blog comments, or any kind of spam.

Abuse reports are a particular kind of feedback whereby users can flag other users' posts as abusive content. Most web sites that allow user generated content either apply some sort of moderation based on abuse reports, such as hiding or deleting the offending content at a defined threshold, or implement a variety of user roles that allow users to govern the site's contents cooperatively.

Spammers' behavior ranges from somehow forcing users to opt in, to cooperatively offering the possibility to opt out, to wildly hiding the sender's identity (including phishing). The most intractable cases can be dealt by reporting the abusive message to hash-sharing systems like, for example, Vipul's Razor for the benefit of other victims. In some cases, there may be a cooperative component on the sender side who will use spam reports to fix or mitigate the problem at its origin; for example, it may use them to detect botnets, educate the sender, or simply unsubscribe the report's originator. Email spam legislation varies by country, forbidding abusive behavior to some extent, and in some other cases it may be worth to legally prosecute spammers and claim damage.

RFC 6650 recommends that recipients of abusive messages report that to their mailbox providers. The provider's abuse-team should determine the best course of action, possibly considering hash-sharing and legal steps. If the sender had subscribed to a Feedback Loop (FBL), the mailbox provider will forward the complaint as a feedback report according to the existing FBL agreement. Otherwise, mailbox providers should determine who is responsible of the abuse and forward the complaint to them. Those recipients of unsolicited abuse reports are actually prospect FBL subscribers, inasmuch as the mailbox provider needs to offer them some means to manage the report stream. On the other hand, mailbox providers can prevent further messages from non-cooperative senders of abusive content.

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Wikipedia