Every .dk domain that delegates its _acme-challenge name to ob0p17pllnr7u9q5whig9h0quz324wqe.acme.pil.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.