Every .dk domain that delegates its _acme-challenge name to bbaf4ca1-b665-4c5d-a3d1-f8f8ee4d0502.0.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.