diff --git a/src/engine/client/library/clientUserInterface/src/shared/widget/CuiWidget3dObjectListViewer.cpp b/src/engine/client/library/clientUserInterface/src/shared/widget/CuiWidget3dObjectListViewer.cpp
index 8030d0999..326078e79 100644
--- a/src/engine/client/library/clientUserInterface/src/shared/widget/CuiWidget3dObjectListViewer.cpp
+++ b/src/engine/client/library/clientUserInterface/src/shared/widget/CuiWidget3dObjectListViewer.cpp
@@ -2708,7 +2708,7 @@ void CuiWidget3dObjectListViewer::addObject    (Object & obj)
 
 	if (hasFlags (F_alterObjects))
 	{
-		if (obj.isInitialized() && (obj.alter(Clock::frameTime()) != AlterResult::cms_kill))
+		if (obj.isInitialized() && !obj.isInWorld() && (obj.alter(Clock::frameTime()) != AlterResult::cms_kill))
 		{
 			obj.conclude();
 		}
diff --git a/src/engine/shared/library/sharedObject/src/shared/ObjectWatcherList.cpp b/src/engine/shared/library/sharedObject/src/shared/ObjectWatcherList.cpp
index a2cb6e673..765c6f293 100644
--- a/src/engine/shared/library/sharedObject/src/shared/ObjectWatcherList.cpp
+++ b/src/engine/shared/library/sharedObject/src/shared/ObjectWatcherList.cpp
@@ -222,7 +222,7 @@ void ObjectWatcherList::alter(real time)
 		// is removed from the list withing its alter()
 	
 		Object * const obj = (*m_alterSafeObjectVector)[i];
-		if (!obj || !obj->isInitialized())
+		if (!obj || !obj->isInitialized() || obj->isInWorld())
 			continue;
 
 		float const alterResult = obj->alter(time);