The Author Domain is the domain name that appears in the visible “From” address of an email (the one users see in their inbox).
For example, in the message From: marketing@example.com, the Author Domain is example.com. It represents the organization or entity that claims responsibility for the email’s content.
In email authentication, the Author Domain plays a critical role because it’s the domain that DMARC policies ultimately protect. When a receiving mail server evaluates an incoming message, it checks whether the technical senders (used by SPF and DKIM) align with this Author Domain.
While SPF and DKIM each authenticate different aspects of a message, DMARC ties them together by requiring alignment with the Author Domain.
If neither SPF nor DKIM aligns, the message fails DMARC, which signals to receiving servers that the email may be fraudulent or spoofed.
The Author Domain is central to brand trust and email identity. It’s what recipients recognize, and what attackers often attempt to impersonate.
By enforcing DMARC policies on your Author Domain, you can prevent others from sending unauthorized messages that appear to come from your brand. This protects customers from phishing and keeps your domain reputation strong.
In other words, understanding and securing your Author Domain is one of the most important steps in safeguarding your email ecosystem.
DMARCeye helps you monitor authentication and alignment results across all your sending sources. By analyzing DMARC reports, it shows whether emails sent on behalf of your Author Domain are passing SPF and DKIM checks, and whether alignment is correctly configured.
With the visibility provided by DMARCeye, you can quickly identify unauthorized senders or misconfigurations that threaten your domain’s credibility, and take steps to maintain full compliance with your DMARC policy.
Sign up for a free trial of DMARCeye today to secure your email domain.
To learn more about DMARC and DMARC-related terms, explore the DMARCeye Glossary.