diff --git a/lean/models/api.py b/lean/models/api.py
index 35863384..3cdbb14f 100644
--- a/lean/models/api.py
+++ b/lean/models/api.py
@@ -55,7 +55,7 @@ class ProjectEncryptionKey(WrappedBaseModel):
     name: str
 
 class QCCollaborator(WrappedBaseModel):
-    uid: int
+    uid: Optional[int]
     liveControl: bool
     permission: str
     profileImage: str