Every .dk domain that delegates its _acme-challenge name to 56d632fc-e7fe-40a9-a0a1-2fcc987d48bf.19.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.