Every .dk domain that delegates its _acme-challenge name to 9ba1cdfd-8ab1-4ec0-939d-8f679ff9391e.stackpath-tls.com. 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.