Spamhaus Announces New DBL Return Codes

Spamhaus announced that it is rolling out two new sets of return codes for its Domain Block List (DBL) beginning July 1, 2014. The first set is used to list malware domains and botnet command and control (C&C) domains. The second set is used to list legitimate domains that are compromised. The announcement from Spamhaus states “This new data makes DBL more effective and versatile yet maintains DBL’s goal for near zero false positives and widespread usability in production environments.” In particular, use of these new codes can enable users of the DBL to identify and remediate compromised users and websites.

For Return Path customers, this data will be valuable because it will provide insight into whether Spamhaus believes a domain is spammy or is legitimate but being abused to send spam (or phish, or as part of a botnet, etc.).

Below is a table of the DBL return codes, taken from the Spamhaus site, with the new codes highlighted. ( Note that return code is being replaced by, since the intent is to identify when a legit redirector or URL shortener is being used to send spam.

dbl_codes (1)

For more information on this change, see the Spamhaus announcement and DBL FAQ, or reach out to your Return Path relationship manager. To understand how email blacklists like this can affect email marketing campaign performance, check out our email blacklist infographic.

minute read

Popular stories



BriteVerify email verification ensures that an email address actually exists in real-time


The #1 global data quality tool used by thousands of Salesforce admins


Insights and deliverability guidance from the only all-in-one email marketing solution

GridBuddy Cloud

Transform how you interact with your data through the versatility of grids.

Return Path

World-class deliverability applications to optimize email marketing programs

Trust Assessments

A revolutionary new solution for assessing Salesforce data quality


Validity for Email

Increase inbox placement and maximize subscriber reach with clean and actionable data

Validity for Data Management

Simplify data management with solutions that improve data quality and increase CRM adoption

Validity for Sales Productivity

Give your sales team back hours per day with tools designed to increase productivity and mitigate pipeline risks in real-time