MarTech Interview with Len Shneyder, VP of Industry Relations at Twilio SendGrid

Domain-based Message Authentication, and Reporting, and Conformance is a policy that adds to SPF and DKIM and gives a receiving set of instructions on what they should do when an email they received fails other authentication checks.
https://martechseries.com/mts-insights/interviews/len-shneyder-twilio-sendgrid/