diff --git a/djaosdb/caosdb_client.py b/djaosdb/caosdb_client.py
index 7360aafcabf4424d62c8ac0485b043ac68b882bf..308941017ee13c7fc7fc8e59c69f1fc59f052571 100644
--- a/djaosdb/caosdb_client.py
+++ b/djaosdb/caosdb_client.py
@@ -214,8 +214,7 @@ class DefaultCaosDBClientDelegate:
                 for p in e.get_properties():
                     row[p.name] = p.value
                     if isinstance(p.value, list):
-                        if len(p.value) == 0:
-                            row[p.name] = None
+                        row[p.name] = json.dumps(p.value)
                 rows.append(row)
             return rows
         rows = container.get_property_values(*projection)