diff --git a/src/blenderbim/blenderbim/bim/__init__.py b/src/blenderbim/blenderbim/bim/__init__.py
index 375343a285..b6413dac28 100644
--- a/src/blenderbim/blenderbim/bim/__init__.py
+++ b/src/blenderbim/blenderbim/bim/__init__.py
@@ -224,7 +224,6 @@ def register():
     bpy.types.Screen.BIMTabProperties = bpy.props.PointerProperty(type=prop.BIMTabProperties)
     bpy.types.Collection.BIMCollectionProperties = bpy.props.PointerProperty(type=prop.BIMCollectionProperties)
     bpy.types.Object.BIMObjectProperties = bpy.props.PointerProperty(type=prop.BIMObjectProperties)
-    bpy.types.Material.BIMObjectProperties = bpy.props.PointerProperty(type=prop.BIMObjectProperties)
     bpy.types.Material.BIMMaterialProperties = bpy.props.PointerProperty(type=prop.BIMMaterialProperties)
     bpy.types.Mesh.BIMMeshProperties = bpy.props.PointerProperty(type=prop.BIMMeshProperties)
     bpy.types.Curve.BIMMeshProperties = bpy.props.PointerProperty(type=prop.BIMMeshProperties)
diff --git a/src/blenderbim/blenderbim/bim/ifc.py b/src/blenderbim/blenderbim/bim/ifc.py
index ea871f1a35..4fbca1cb3a 100644
--- a/src/blenderbim/blenderbim/bim/ifc.py
+++ b/src/blenderbim/blenderbim/bim/ifc.py
@@ -358,7 +358,8 @@ class IfcStore:
     def purge_blender_ifc_data(obj: IFC_CONNECTED_TYPE) -> None:
         if isinstance(obj, bpy.types.Material):
             obj.BIMMaterialProperties.ifc_style_id = 0
-        obj.BIMObjectProperties.ifc_definition_id = 0
+        else:
+            obj.BIMObjectProperties.ifc_definition_id = 0
 
     @staticmethod
     def execute_ifc_operator(operator: bpy.types.Operator, context: bpy.types.Context, is_invoke=False):