diff --git a/addons/cetmix_tower_yaml/migrations/16.0.1.4.1/post-migration.py b/addons/cetmix_tower_yaml/migrations/16.0.1.4.1/post-migration.py
new file mode 100644
index 0000000..8238759
--- /dev/null
+++ b/addons/cetmix_tower_yaml/migrations/16.0.1.4.1/post-migration.py
@@ -0,0 +1,19 @@
+def migrate(cr, version):
+    """
+    Normalize existing license values to lowercase.
+    Runs only on upgrade (version != False).
+    """
+    if not version:
+        return
+    # Skip rows already lowercase for efficiency
+    cr.execute(
+        """
+        UPDATE cx_tower_yaml_manifest_tmpl
+           SET license = LOWER(TRIM(license))
+         WHERE license IS NOT NULL
+           AND (
+                license <> LOWER(license)
+             OR license <> TRIM(license)
+           )
+    """
+    )