diff --git a/nomad/app/v1/routers/datasets.py b/nomad/app/v1/routers/datasets.py
index 92cda30c332451ee2936f5ff6b36ec4fe9d9813c..fff8ab95d5ac78b439574ede950a4d00f96df483 100644
--- a/nomad/app/v1/routers/datasets.py
+++ b/nomad/app/v1/routers/datasets.py
@@ -255,7 +255,7 @@ class DatasetResponse(BaseModel):
 
 
 class DatasetType(str, enum.Enum):
-    owned = ('owned',)
+    owned = 'owned'
     foreign = 'foreign'