Every .dk domain that delegates its _acme-challenge name to a78de609-9e67-4dea-9c4b-ff0ebc47a097.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.