diff --git a/raillabel/format/bbox.py b/raillabel/format/bbox.py
index b30b1e6..c07939a 100644
--- a/raillabel/format/bbox.py
+++ b/raillabel/format/bbox.py
@@ -23,7 +23,7 @@ class Bbox:
     size: Size2d
     "The dimensions of the bbox in pixels from the top left corner to the bottom right corner."
 
-    object: UUID
+    object_uid: UUID
     "The uid of the object, this annotation belongs to."
 
     sensor: str
@@ -38,7 +38,7 @@ def from_json(cls, json: JSONBbox, object_uid: UUID) -> Bbox:
         return Bbox(
             pos=Point2d.from_json((json.val[0], json.val[1])),
             size=Size2d.from_json((json.val[2], json.val[3])),
-            object=object_uid,
+            object_uid=object_uid,
             sensor=json.coordinate_system,
             attributes=_attributes_from_json(json.attributes),
         )
diff --git a/raillabel/format/cuboid.py b/raillabel/format/cuboid.py
index ff6f9bc..886ea3f 100644
--- a/raillabel/format/cuboid.py
+++ b/raillabel/format/cuboid.py
@@ -28,7 +28,7 @@ class Cuboid:
     size: Size3d
     "The size of the cuboid in meters."
 
-    object: UUID
+    object_uid: UUID
     "The uid of the object, this annotation belongs to."
 
     sensor: str
@@ -44,7 +44,7 @@ def from_json(cls, json: JSONCuboid, object_uid: UUID) -> Cuboid:
             pos=Point3d.from_json((json.val[0], json.val[1], json.val[2])),
             quat=Quaternion.from_json((json.val[3], json.val[4], json.val[5], json.val[6])),
             size=Size3d.from_json((json.val[7], json.val[8], json.val[9])),
-            object=object_uid,
+            object_uid=object_uid,
             sensor=json.coordinate_system,
             attributes=_attributes_from_json(json.attributes),
         )
diff --git a/raillabel/format/poly2d.py b/raillabel/format/poly2d.py
index 1a99b3d..cbf5b6f 100644
--- a/raillabel/format/poly2d.py
+++ b/raillabel/format/poly2d.py
@@ -22,7 +22,7 @@ class Poly2d:
     closed: bool
     "If True, this object represents a polygon and if False, it represents a polyline."
 
-    object: UUID
+    object_uid: UUID
     "The uid of the object, this annotation belongs to."
 
     sensor: str
@@ -40,7 +40,7 @@ def from_json(cls, json: JSONPoly2d, object_uid: UUID) -> Poly2d:
                 for i in range(0, len(json.val), 2)
             ],
             closed=json.closed,
-            object=object_uid,
+            object_uid=object_uid,
             sensor=json.coordinate_system,
             attributes=_attributes_from_json(json.attributes),
         )
diff --git a/raillabel/format/poly3d.py b/raillabel/format/poly3d.py
index 45d7f34..3561d61 100644
--- a/raillabel/format/poly3d.py
+++ b/raillabel/format/poly3d.py
@@ -22,7 +22,7 @@ class Poly3d:
     closed: bool
     "If True, this object represents a polygon and if False, it represents a polyline."
 
-    object: UUID
+    object_uid: UUID
     "The uid of the object, this annotation belongs to."
 
     sensor: str
@@ -40,7 +40,7 @@ def from_json(cls, json: JSONPoly3d, object_uid: UUID) -> Poly3d:
                 for i in range(0, len(json.val), 3)
             ],
             closed=json.closed,
-            object=object_uid,
+            object_uid=object_uid,
             sensor=json.coordinate_system,
             attributes=_attributes_from_json(json.attributes),
         )
diff --git a/raillabel/format/seg3d.py b/raillabel/format/seg3d.py
index c4647e0..c201f4f 100644
--- a/raillabel/format/seg3d.py
+++ b/raillabel/format/seg3d.py
@@ -18,7 +18,7 @@ class Seg3d:
     point_ids: list[int]
     "The list of point indices."
 
-    object: UUID
+    object_uid: UUID
     "The uid of the object, this annotation belongs to."
 
     sensor: str
@@ -32,7 +32,7 @@ def from_json(cls, json: JSONVec, object_uid: UUID) -> Seg3d:
         """Construct an instant of this class from RailLabel JSON data."""
         return Seg3d(
             point_ids=[int(point_id) for point_id in json.val],
-            object=object_uid,
+            object_uid=object_uid,
             sensor=json.coordinate_system,
             attributes=_attributes_from_json(json.attributes),
         )
diff --git a/tests/test_raillabel/format/test_bbox.py b/tests/test_raillabel/format/test_bbox.py
index fb39bd2..a22a368 100644
--- a/tests/test_raillabel/format/test_bbox.py
+++ b/tests/test_raillabel/format/test_bbox.py
@@ -45,7 +45,7 @@ def bbox(
         size=size2d,
         sensor="rgb_middle",
         attributes=attributes_multiple_types,
-        object=object_person_uid,
+        object_uid=object_person_uid,
     )
 
 
diff --git a/tests/test_raillabel/format/test_cuboid.py b/tests/test_raillabel/format/test_cuboid.py
index 855777c..7d6614b 100644
--- a/tests/test_raillabel/format/test_cuboid.py
+++ b/tests/test_raillabel/format/test_cuboid.py
@@ -48,7 +48,7 @@ def cuboid(
         size=size3d,
         sensor="lidar",
         attributes=attributes_multiple_types,
-        object=object_person_uid,
+        object_uid=object_person_uid,
     )
 
 
diff --git a/tests/test_raillabel/format/test_poly2d.py b/tests/test_raillabel/format/test_poly2d.py
index d021f15..8ead75a 100644
--- a/tests/test_raillabel/format/test_poly2d.py
+++ b/tests/test_raillabel/format/test_poly2d.py
@@ -47,7 +47,7 @@ def poly2d(
         closed=True,
         sensor="rgb_middle",
         attributes=attributes_multiple_types,
-        object=object_track_uid,
+        object_uid=object_track_uid,
     )
 
 
diff --git a/tests/test_raillabel/format/test_poly3d.py b/tests/test_raillabel/format/test_poly3d.py
index 1467037..a3f3b75 100644
--- a/tests/test_raillabel/format/test_poly3d.py
+++ b/tests/test_raillabel/format/test_poly3d.py
@@ -46,7 +46,7 @@ def poly3d(
         closed=True,
         sensor="lidar",
         attributes=attributes_multiple_types,
-        object=object_track_uid,
+        object_uid=object_track_uid,
     )
 
 
diff --git a/tests/test_raillabel/format/test_seg3d.py b/tests/test_raillabel/format/test_seg3d.py
index cd91e03..24a3853 100644
--- a/tests/test_raillabel/format/test_seg3d.py
+++ b/tests/test_raillabel/format/test_seg3d.py
@@ -40,7 +40,7 @@ def seg3d(
         point_ids=[1234, 5678],
         sensor="lidar",
         attributes=attributes_multiple_types,
-        object=object_person_uid,
+        object_uid=object_person_uid,
     )