Domain-based Message Authentication, Reporting and Conformance (DMARC) is an email-validation system designed to detect and prevent email spoofing.
It provides a mechanism which allows a receiving organization to check that incoming mail from a domain is authorized by that domain's administrators and that the email (including attachments) has not been modified during transport. It is thus intended to combat certain techniques often used in phishing and email spam, such as emails with forged sender addresses that appear to originate from legitimate organizations. DMARC is specified in RFC 7489.

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