diff --git a/iat-verifier/tests/data/cca_realm2.pem b/iat-verifier/tests/data/cca_realm2.pem
new file mode 100644
index 0000000..86a96fd
--- /dev/null
+++ b/iat-verifier/tests/data/cca_realm2.pem
@@ -0,0 +1,6 @@
+-----BEGIN EC PRIVATE KEY-----
+MIGkAgEBBDAUpTBCqGYMwJ/qywlXHrHwZec2dLYE9xNYjtR6BEjLEC1NYJMDlUfk
+gCQORURs0zigBwYFK4EEACKhZANiAASBGViAoiB/uVYDKjy5f12lr3Jv/LcV7hZH
+hKf7FsBglr3ZRioyZQspEqhVFXDW6h87LR99qKJ1+gAzDwB4YYvD4UlUnIFw0y7F
+WJCn+ex4nx8YrpLrFdIir5cdlxyWWvE=
+-----END EC PRIVATE KEY-----
diff --git a/iat-verifier/tests/test_utils.py b/iat-verifier/tests/test_utils.py
index e05c953..8059139 100644
--- a/iat-verifier/tests/test_utils.py
+++ b/iat-verifier/tests/test_utils.py
@@ -45,7 +45,7 @@
     token_map = read_token_map(source_path)
     return convert_map_to_token_bytes(token_map, verifier, add_p_header)
 
-def create_token_file(data_dir, source_name, verifier, dest_path, *, add_p_header=False):
+def create_token_file(data_dir, source_name, verifier, dest_path, *, add_p_header=True):
     """Create a cbor token from a yaml file and write it to a file
     """
     token = create_token(
diff --git a/iat-verifier/tests/test_verifier.py b/iat-verifier/tests/test_verifier.py
index bb03513..2f45d66 100644
--- a/iat-verifier/tests/test_verifier.py
+++ b/iat-verifier/tests/test_verifier.py
@@ -24,6 +24,7 @@
 KEYFILE = os.path.join(DATA_DIR, 'key.pem')
 KEYFILE_CCA_PLAT = os.path.join(DATA_DIR, 'cca_platform.pem')
 KEYFILE_CCA_REALM = os.path.join(DATA_DIR, 'cca_realm.pem')
+KEYFILE_CCA_REALM2= os.path.join(DATA_DIR, 'cca_realm2.pem')
 KEYFILE_ALT = os.path.join(DATA_DIR, 'key-alt.pem')
 
 class TestIatVerifier(unittest.TestCase):
@@ -81,6 +82,7 @@
         cose_alg=AttestationTokenVerifier.COSE_ALG_ES256
         signing_key = read_keyfile(KEYFILE, method)
         realm_token_key = read_keyfile(KEYFILE_CCA_REALM, method)
+        realm_token_key2 = read_keyfile(KEYFILE_CCA_REALM2, method)
         platform_token_key = read_keyfile(KEYFILE_CCA_PLAT, method)
 
         create_and_read_iat(
@@ -91,6 +93,7 @@
                 cose_alg=cose_alg,
                 signing_key=signing_key,
                 configuration=self.config))
+
         create_and_read_iat(
             DATA_DIR,
             'valid-cca-token.yaml',
@@ -115,6 +118,20 @@
 
         with self.assertRaises(ValueError) as test_ctx:
             create_and_read_iat(
+                DATA_DIR,
+                'valid-cca-token.yaml',
+                CCATokenVerifier(
+                    realm_token_method=method,
+                    realm_token_cose_alg=AttestationTokenVerifier.COSE_ALG_ES384,
+                    realm_token_key=realm_token_key2,
+                    platform_token_method=method,
+                    platform_token_cose_alg=AttestationTokenVerifier.COSE_ALG_ES384,
+                    platform_token_key=platform_token_key,
+                    configuration=self.config))
+        self.assertIn("Realm signature doesn't match Realm Public Key claim in Realm token", test_ctx.exception.args[0])
+
+        with self.assertRaises(ValueError) as test_ctx:
+            create_and_read_iat(
             DATA_DIR,
                 'invalid-profile-id.yaml',
                 PSAIoTProfile1TokenVerifier(method=method,