diff --git a/33128/r18/TS33128Payloads.asn b/33128/r18/TS33128Payloads.asn
index 91ae2420f3e1bd6b3a3b585eb75789089e498c7c..c7975b960f3e6b084ec876bd2fbde668adccda44 100644
--- a/33128/r18/TS33128Payloads.asn
+++ b/33128/r18/TS33128Payloads.asn
@@ -281,9 +281,10 @@ XIRIEvent ::= CHOICE
 
 IRIPayload ::= SEQUENCE
 {
-    iRIPayloadOID       [1] RELATIVE-OID,
-    event               [2] IRIEvent,
-    targetIdentifiers   [3] SEQUENCE OF IRITargetIdentifier OPTIONAL
+    iRIPayloadOID          [1] RELATIVE-OID,
+    event                  [2] IRIEvent,
+    targetIdentifiers      [3] SEQUENCE OF IRITargetIdentifier OPTIONAL,
+    mediatedFromIndicator  [4] MediatedFromIndicator OPTIONAL
 }
 
 IRIEvent ::= CHOICE
@@ -534,6 +535,11 @@ IRITargetIdentifier ::= SEQUENCE
     provenance                                          [2] TargetIdentifierProvenance OPTIONAL
 }
 
+MediatedFromIndicator ::= CHOICE
+{
+    xIRIRelativeOID [1] RELATIVE-OID
+}
+
 -- ==============
 -- HI3 CC payload
 -- ==============