Every .dk domain that delegates its _acme-challenge name to 81f2ef2f-2ac0-4477-9c1a-cc22810f186c.auth.acme-dns.io. 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.