diff --git a/src/App/DocumentObject.cpp b/src/App/DocumentObject.cpp
index 2950697434..708b6ea3b9 100644
--- a/src/App/DocumentObject.cpp
+++ b/src/App/DocumentObject.cpp
@@ -292,6 +292,15 @@ std::string DocumentObject::getFullLabel() const {
     return name;
 }
 
+const char* DocumentObject::getDagKey() const
+{
+    if(!pcNameInDocument)
+    {
+        return nullptr;
+    }
+    return pcNameInDocument->c_str();
+}
+
 const char *DocumentObject::getNameInDocument() const
 {
     // Note: It can happen that we query the internal name of an object even if it is not
@@ -808,7 +817,7 @@ DocumentObject *DocumentObject::getSubObject(const char *subname,
         if(outList.size()!=_outListMap.size()) {
             _outListMap.clear();
             for(auto obj : outList)
-                _outListMap[obj->getNameInDocument()] = obj;
+                _outListMap[obj->getDagKey()] = obj;
         }
         auto it = _outListMap.find(name.c_str());
         if(it != _outListMap.end())
diff --git a/src/App/DocumentObject.h b/src/App/DocumentObject.h
index a274a60c0c..b9b745ad54 100644
--- a/src/App/DocumentObject.h
+++ b/src/App/DocumentObject.h
@@ -132,6 +132,8 @@ public:
     DocumentObject();
     ~DocumentObject() override;
 
+    /// returns a value that uniquely identifies this DocumentObject.
+    const char* getDagKey() const;
     /// returns the name which is set in the document for this object (not the name property!)
     const char *getNameInDocument() const;
     /// Return the object ID that is unique within its owner document
diff --git a/src/App/Link.cpp b/src/App/Link.cpp
index a63cd4bf8f..4328a2ebe1 100644
--- a/src/App/Link.cpp
+++ b/src/App/Link.cpp
@@ -468,7 +468,7 @@ void LinkBaseExtension::setOnChangeCopyObject(
         }
     }
 
-    const char *key = flags.testFlag(OnChangeCopyOptions::ApplyAll) ? "*" : parent->getNameInDocument();
+    const char *key = flags.testFlag(OnChangeCopyOptions::ApplyAll) ? "*" : parent->getDagKey();
     if (external)
         prop->setValue(key, exclude ? "" : "+");
     else
diff --git a/src/Gui/ViewProviderLink.cpp b/src/Gui/ViewProviderLink.cpp
index c121fe91b2..61a68d6465 100644
--- a/src/Gui/ViewProviderLink.cpp
+++ b/src/Gui/ViewProviderLink.cpp
@@ -225,7 +225,7 @@ public:
     }
 
     const char *getLinkedName() const {
-        return pcLinked->getObject()->getNameInDocument();
+        return pcLinked->getObject()->getDagKey();
     }
 
     const char *getLinkedLabel() const {