diff --git a/services/src/main/java/org/fao/geonet/api/es/EsHTTPProxy.java b/services/src/main/java/org/fao/geonet/api/es/EsHTTPProxy.java
index caf3c9ea8ad..dbb861fe95f 100644
--- a/services/src/main/java/org/fao/geonet/api/es/EsHTTPProxy.java
+++ b/services/src/main/java/org/fao/geonet/api/es/EsHTTPProxy.java
@@ -690,7 +690,7 @@ private void processResponse(ServiceContext context, HttpSession httpSession,
                     addRelatedTypes(doc, relatedTypes, context);
                 }
 
-                if (doc.has("_source")) {
+                if (doc.has("_source") && doc.get("_source").has("documentStandard") ) {
                     ObjectNode sourceNode = (ObjectNode) doc.get("_source");
 
                     String metadataSchema = doc.get("_source").get("documentStandard").asText();