Every .dk domain that delegates its _acme-challenge name to 860f1d7d-3b23-467c-8a11-a73fb7a3eed7.4.authorize.certificatemanager.goog. Such CNAMEs hand DNS-01 certificate validation to a shared service, so this list shows who issues TLS certificates through it. Data comes from our own scanners, which re-resolve every .dk domain in the zone roughly once a week.