diff --git a/tests/unit/specs/utils/datashare_index_mappings.json b/tests/unit/specs/utils/datashare_index_mappings.json
index 11b44a6c12..427f813a17 100644
--- a/tests/unit/specs/utils/datashare_index_mappings.json
+++ b/tests/unit/specs/utils/datashare_index_mappings.json
@@ -82,7 +82,7 @@
     "join": {
       "type": "join",
       "relations": {
-        "Document": "NamedEntity"
+        "Document": [ "NamedEntity", "Duplicate" ]
       }
     },
     "mention": {