What is an Organizational Domain?

When reviewing DMARC you will see Organizational Domain mentioned often. An Organizational domain is a top-level domain (TLD) + 1 atom.

For example:

• support.agari.com = agari.com
• agari.co.uk= agari.co.uk
• just.an.example.ne.jp = example.ne.jp

DMARC will use publicsuffix.org for the TLD list.