The Document Metadata Notification Broker that supports this option shall accept and process subscription that uses Folder metadata as filter parameters and shall be able to send notifications based on Folder’s metadata publication when existing subscriptions are matched.  Refer to ITI TF-2b:3.52.4.1.3.1 and 3.52.5.2.2 and 3.53.4.1.2 a match can occur for an update of a folder already existing: e.g. when a document stored in a folder is replaced there is an update to the folder state that SHALL be reported. It is likely that the Document Metadata Notification Broker actor will maintain status of existing folders rather than making GetFolders queries [ITI-18] to determine folder status. 