Every .dk domain that delegates its _acme-challenge name to 125fe6d9-9e5a-409e-9f95-4e8e44d66d3b.trustzonevalidation.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.