diff --git a/src/ifcopenshell-python/ifcopenshell/api/system/assign_system.py b/src/ifcopenshell-python/ifcopenshell/api/system/assign_system.py
index 113e9e3b0a..8906a01a7d 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/system/assign_system.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/system/assign_system.py
@@ -36,6 +36,7 @@ ASSIGNABLE_DICT = {
     ),
     "IfcDistributionSystem": ("IfcDistributionElement",),
     "IfcStructuralAnalysisModel": ("IfcStructuralMember", "IfcStructuralConnection"),
+    "IfcSystem": ("IfcProduct",),
     "IfcGroup": ("IfcObjectDefinition",),
 }