Definition
When a recipient marks your email as spam, the ISP sends a report through the feedback loop. Failing to suppress that address is considered FBL abuse and damages your sender reputation. Common examples include: not having FBL processing configured at all, processing FBL data slowly, continuing to send to known complainers, and not honouring the one-click unsubscribe header. ISPs monitor how quickly and thoroughly you process FBL data. Consistent abuse can lead to blacklisting and permanent inbox placement issues.
Related Glossary Terms
Abuse Complaint
An abuse complaint is a report from a recipient who marks an email as spam, which negatively affects sender reputation and deliverability.
Alt Text
Alt text is the written alternative to an image in an email, displayed when images are blocked, slow to load, or consumed by screen readers.
Anonymized Data
Anonymized data is email subscriber or interaction data that has been stripped of personally identifiable information so individuals cannot be re-identified.
AOL Mail for Email Marketers
AOL Mail is a legacy email provider with specific deliverability requirements and rendering quirks, now operating as part of the Yahoo+AOL network under shared infrastructure.
Email Authentication Protocols
Email authentication protocols are technical standards that verify the identity of an email sender, helping mailbox providers distinguish legitimate mail from spam and phishing.
BIMI
BIMI (Brand Indicators for Message Identification) is an email standard that allows brands to display their logo next to their emails in supported email clients. It requires DMARC enforcement at quarantine or reject policy.