Spam Resource: All Things Deliverability

Validity (and before that, Return Path) has long offered access to various bits of reputation data to email users via DNS, primarily utilized via a particular  SpamAssassin plugin . Checks include whether or not an IP address is on the Validity Certification whitelist, on the "Validity Safe" (aka Habeas) whitelist, or is on the "Validity RPBL" (Return Path Reputation Netw…