diff --git a/docs/managing-remotes.rst b/docs/managing-remotes.rst
index ccb7313e..e3b13d52 100644
--- a/docs/managing-remotes.rst
+++ b/docs/managing-remotes.rst
@@ -90,6 +90,12 @@ the local datastore as well. If the ``owner`` option is not set (defaulting to
 ``root@pam``) or is set to something other than the configuring user,
 ``Datastore.Modify`` is required as well.
 
+If the ``groups`` option is set, only backup groups matching at least one of
+the specified criteria (backup type, full group identifier, or a regular
+expression matched against the full group identifier) are synced. The same
+filter is applied to local groups for handling of the ``remove-vanished``
+option.
+
 .. note:: A sync job can only sync backup groups that the configured remote's
   user/API token can read. If a remote is configured with a user/API token that
   only has ``Datastore.Backup`` privileges, only the limited set of accessible