Engagement - Requirements for a DMARC policy to pass for sends through the Marketing Cloud Enagagement

For DMARC to pass on Marketing Cloud sends, at least one of the following two alignment identifiers must pass. Some email providers apply a stricter standard requiring both SPF and DKIM to align simultaneously.

Identifier 1: SPF Alignment

SPF alignment requires the following two domains to match:

• The From address domain (the domain in the visible sender address)
• The Return-Path domain (also called the Bounce Host or Bounce Domain)

The Return-Path domain is also sometimes called the Bounce Host or Bounce Domain. 

Identifier 2: DKIM Alignment

DKIM alignment requires the following two domains to match:

• The From address domain
• The DKIM signature domain (the `d=` value in the DKIM header, e.g., `d=yourdomain.com`)

Some email providers apply a stricter standard -- where both SPF and DKIM must align. When the authenticated sending domain differs from the SAP domain, SPF will be out of alignment because the bounce domain will not match the sending domain. This can cause message rejections at stricter email domains. 

Multi-Bounce Domain support can be enabled to have bounce domains be set on a per-message basis to reflect each From address's domain. The bounce domain is generated by prefixing the authenticated domain with bounce. Please open a support case to enable Multi-Bounce domain support.