diff --git a/data_store/dto/annotation.py b/data_store/dto/annotation.py
index afeafcd..67c9ddf 100644
--- a/data_store/dto/annotation.py
+++ b/data_store/dto/annotation.py
@@ -13,17 +13,17 @@ from .point_of_view_enum import PointOfViewEnum
 class Annotation(TypeCheckingBaseModel):
     """Data Transfer Object representing an Annotation."""
 
-    angle: AngleEnum
+    angle: AngleEnum | None
     angle_uncertainty: bool
-    colour: ColourEnum
+    colour: ColourEnum | None
     colour_uncertainty: bool
-    contact: ContactEnum
+    contact: ContactEnum | None
     contact_uncertainty: bool
-    depth: DepthEnum
+    depth: DepthEnum | None
     depth_uncertainty: bool
-    distance: DistanceEnum
+    distance: DistanceEnum | None
     distance_uncertainty: bool
-    lighting: LightingEnum
+    lighting: LightingEnum | None
     lighting_uncertainty: bool
-    point_of_view: PointOfViewEnum
+    point_of_view: PointOfViewEnum | None
     point_of_view_uncertainty: bool