diff --git a/weldx/tests/transformations/test_cs_manager.py b/weldx/tests/transformations/test_cs_manager.py
index 34276b8e8..302dbb563 100644
--- a/weldx/tests/transformations/test_cs_manager.py
+++ b/weldx/tests/transformations/test_cs_manager.py
@@ -737,6 +737,18 @@ def test_comparison_wrong_type():
     assert (csm != 4) is True
 
 
+def test_comparison_data():
+    csm1 = tf.CoordinateSystemManager("root", "csm")
+    csm2 = tf.CoordinateSystemManager("root", "csm")
+    data = np.arange(12).reshape((4, 3))
+    csm1.assign_data(data, data_name="foo", reference_system="root")
+    csm2.assign_data(data, data_name="foo", reference_system="root")
+
+    assert csm1 == csm2
+    csm2.assign_data(data, data_name="bar", reference_system="root")
+    assert csm1 != csm2
+
+
 # test_time_union ----------------------------------------------------------------------
 
 
diff --git a/weldx/transformations/cs_manager.py b/weldx/transformations/cs_manager.py
index e37abccbd..1ae944e2f 100644
--- a/weldx/transformations/cs_manager.py
+++ b/weldx/transformations/cs_manager.py
@@ -149,7 +149,6 @@ def __repr__(self):
 
     def __eq__(self, other: Any):
         """Test equality of CSM instances."""
-        # todo: also check data  -> add tests
         if not isinstance(other, self.__class__):
             return False
 
@@ -175,17 +174,19 @@ def __eq__(self, other: Any):
         for node in graph_0.nodes:
             if node not in graph_1.nodes:
                 return False
+            n0 = graph_0.nodes[node]
+            n1 = graph_1.nodes[node]
+            if not util.compare_nested(n0, n1):
+                return False
 
         # check edges
         for edge in graph_0.edges:
             if edge not in graph_1.edges:
                 return False
 
-        # check coordinate systems
-        for edge in graph_0.edges:
-            lcs_0 = self.graph.edges[(edge[0], edge[1])]["transformation"]
-            lcs_1 = other.graph.edges[(edge[0], edge[1])]["transformation"]
-            if lcs_0 != lcs_1:
+            e0 = graph_0.edges[edge]
+            e1 = graph_1.edges[edge]
+            if not util.compare_nested(e0, e1):
                 return False
 
         return True