Every .dk domain that delegates its _acme-challenge name to 8556edc9-da74-4ec8-8e94-af2aa8f4d178.acme.aau.dk. 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.