Acceptable Use
Effective April 16, 2026
Shared-IP email only works when every member sends responsibly. These rules are how we protect the pool's reputation on your behalf.
Send on your own behalf
The relay is for mail originating from you — transactional, operational, or personal correspondence sent from the domain you enrolled. Do not resell relay credentials, relay mail for third parties, or use the service as a public-facing SMTP gateway.
No unsolicited bulk mail
You must have prior permission from every recipient. Scraped lists, purchased lists, and "opt-out only" mailing strategies are prohibited. We enforce volume caps, bounce rate thresholds, domain-spray detection, and velocity rules; crossing any of them will cost your DID its reputation labels and may trigger automatic suspension.
Prohibited content
- Phishing, credential harvesting, or impersonation of third parties.
- Malware, ransomware, exploit payloads, or links to them.
- Fraud, scams, illegal goods, or content that violates US federal or Washington state law.
- Content targeting or harassing an individual, or inciting violence against a group.
- Unauthorized use of another person's name, likeness, or identity.
One-click unsubscribe
Every bulk message sent through the relay carries RFC 8058 List-Unsubscribe and List-Unsubscribe-Post headers. When a recipient triggers an unsubscribe, that address is added to your suppression list and further bulk attempts to send to it will be quietly dropped. Attempting to work around the suppression list — by re-enrolling the same address under a variant, rotating domains, or stripping the header — is a terminating offense.
User-initiated transactional mail (login links, password resets, MFA codes, address verification) is exempt from both behaviors. Tag those messages with the X-Atmos-Category header (login-link, password-reset, mfa-otp, or verification) and the relay will skip the unsubscribe header and bypass the suppression list, so an accidental click on a previous message can't lock the recipient out of their own auth flow. Untagged mail defaults to bulk — the strict policy above applies.
Abuse complaints
If we receive an abuse report about mail from your DID we may ask you to explain it. Failure to respond within a reasonable window (48 hours by default) can result in suspension pending review. Report abuse by others to abuse@atmos.email.
What happens when you break the rules
We apply the lightest intervention that fixes the problem. In order of increasing severity: a reputation label that throttles hourly volume; a temporary suspension pending operator review; permanent removal of the DID and its domains from the relay. Appeals go to postmaster@atmos.email.