Every .dk domain that delegates its _acme-challenge name to ac488553-e427-41f5-9d73-a1401f090b41.9.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.