--- a/mod_firewall/README.markdown	Thu Mar 17 12:09:20 2016 +0000
+++ b/mod_firewall/README.markdown	Thu Mar 17 12:10:50 2016 +0000
@@ -344,6 +344,11 @@
   `MARK_ORIGIN=mark`        Marks the originating session with the given flag.
   `UNMARK_ORIGIN=mark`      Removes the given mark from the origin session (if it is set).
 
+**Note:** Marks apply to sessions, not JIDs. E.g. if marking in a rule that matches a stanza received
+over s2s, it is the s2s session that is marked.
+
+It is possible to have multiple marks on an origin at any given time.
+
 ### Informational
 
   Action          Description