diff --git a/whelktool/src/main/resources/bulk-change-scripts/merge.groovy b/whelktool/src/main/resources/bulk-change-scripts/merge.groovy
index 8a4fa40dbe..c4a96bc897 100644
--- a/whelktool/src/main/resources/bulk-change-scripts/merge.groovy
+++ b/whelktool/src/main/resources/bulk-change-scripts/merge.groovy
@@ -16,6 +16,11 @@ if (!deprecateId || !keepId) return
 List<String> obsoleteThingUris = []
 
 selectByIds([deprecateId]) { obsolete ->
+    // Assert that the resource to deprecate is not the same as the one to be kept
+    if (obsolete.doc.getThingIdentifiers().first() == keepId) {
+        return
+    }
+
     obsoleteThingUris = obsolete.doc.getThingIdentifiers()
 
     selectByIds(obsolete.getDependers()) { depender ->