diff --git a/tests/test_metadata_serialization.py b/tests/test_metadata_serialization.py
index fd212974..a234e752 100644
--- a/tests/test_metadata_serialization.py
+++ b/tests/test_metadata_serialization.py
@@ -319,6 +319,13 @@ def test_invalid_delegated_role_serialization(self, test_case_data: str):
 
     invalid_delegations: utils.DataSet = {
         "empty delegations": "{}",
+        "missing keys": '{ "roles": [ \
+                {"keyids": ["keyid"], "name": "a", "terminating": true, "paths": ["fn1"], "threshold": 3}, \
+                {"keyids": ["keyid2"], "name": "b", "terminating": true, "paths": ["fn2"], "threshold": 4} ] \
+            }',
+        "missing roles": '{"keys": { \
+                "keyid1" : {"keytype": "rsa", "scheme": "rsassa-pss-sha256", "keyval": {"public": "foo"}}, \
+                "keyid2" : {"keytype": "ed25519", "scheme": "ed25519", "keyval": {"public": "bar"}}}}',
         "bad keys": '{"keys": "foo", \
             "roles": [{"keyids": ["keyid"], "name": "a", "paths": ["fn1", "fn2"], "terminating": false, "threshold": 3}]}',
         "bad roles": '{"keys": {"keyid" : {"keytype": "rsa", "scheme": "rsassa-pss-sha256", "keyval": {"public": "foo"}}}, \