Every .dk domain that delegates its _acme-challenge name to 68dbf209-2d9e-48c4-b795-840a0d25dbac.1.authorize.certificatemanager.goog. 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.