Every .dk domain that delegates its _acme-challenge name to e005241b-466b-4bf9-9f87-9748c4501c97.auth.acme-challenge.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.