by subdomain ü Group source IPs by organization domain. (It may be divided by smaller meaningful groups such as transactional IPs and promotional IPs .) ü Analyze the pass rate of DMARC, DKIM, and SPF separately. ü Check if DKIM and SPF are aligned with DMARC domain. ü Check if DMARC failed emails pass ARC. I recommend using the DMARC report analysis tool. However, it is better to use it after understanding the important points for you.