This indicator expressed as a URI indicates:

A certificate validity status information services issuing and signing Certificate Revocation Lists (CRLs) and being part of a service from a (qualified) trust service provider issuing qualified certificates, in accordance with the applicable national legislation in the territory identified by the TL Scheme territory (see clause 5.3.10) or with Regulation (EU) No 910/2014 [i.10] whichever is in force at the time of provision.