diff --git a/opentaxii/persistence/sqldb/api.py b/opentaxii/persistence/sqldb/api.py
index 4ce29538..69bea7b1 100644
--- a/opentaxii/persistence/sqldb/api.py
+++ b/opentaxii/persistence/sqldb/api.py
@@ -1004,7 +1004,7 @@ def add_objects(
                         id=obj["id"],
                         collection_id=collection_id,
                         type=obj["id"].split("--")[0],
-                        spec_version=obj["spec_version"],
+                        spec_version=obj.get("spec_version", 2.1),
                         date_added=datetime.datetime.now(datetime.timezone.utc),
                         version=version,
                         serialized_data={