How do MBPs evaluate transparency in sender metadata?

MBPs evaluate sender metadata transparency by checking for consistency across headers, authentication, and historical patterns. They verify that From domains align with authentication, that header information is properly formatted, and that identification is consistent over time.

Transparency signals include stable From domains, properly configured authentication matching visible identity, accurate timestamps, and headers that honestly represent message purpose.

Red flags include mismatched identities, frequently changing From information, headers designed to obscure origin, and patterns matching known deceptive techniques. These trigger increased scrutiny and filtering.