--- 
+++ 
@@ -18,6 +18,9 @@
         }
         if (plotState != null && hotspot != null) {
             ChartRenderingInfo owner = plotState.getOwner();
+                if (owner == null) {
+                    return state;
+                }
                 EntityCollection entities = owner.getEntityCollection();
                 if (entities != null) {
                     entities.add(new AxisLabelEntity(this, hotspot, 