diff --git a/federation/tests/entities/diaspora/test_entities.py b/federation/tests/entities/diaspora/test_entities.py
index cc43e32..cfed7fd 100644
--- a/federation/tests/entities/diaspora/test_entities.py
+++ b/federation/tests/entities/diaspora/test_entities.py
@@ -7,6 +7,7 @@ from federation.entities.base import Profile
 from federation.entities.diaspora.entities import (
     DiasporaComment, DiasporaPost, DiasporaLike, DiasporaRequest, DiasporaProfile, DiasporaRetraction,
 )
+from federation.exceptions import SignatureVerificationError
 from federation.tests.fixtures.keys import get_dummy_private_key
 
 
@@ -127,3 +128,25 @@ class TestDiasporaRelayableEntitySigning():
                                    "Q0t-vWGl8cgSS0_34mvvqX-HKUdmun2vQ50bPckNLoj3hDI6HcmZ8qFf_xx8y1BbE0zx5rTo7yOlWq8Y" \
                                    "sC28oRHqHpIzOfhkIHyt-hOjO_mpuZLd7qOPfIySnGW6hM1iKewoJVDuVMN5w5VB46ETRum8JpvTQO8i" \
                                    "DPB-ZqbqcEasfm2CQIxVLA=="
+
+
+class TestDiasporaRelayableEntityValidate():
+    def test_raises_if_no_sender_key(self):
+        entity = DiasporaComment()
+        with pytest.raises(SignatureVerificationError):
+            entity._validate_signatures()
+
+    @patch("federation.entities.diaspora.entities.verify_relayable_signature")
+    def test_calls_verify_signature(self, mock_verify):
+        entity = DiasporaComment()
+        entity._sender_key = "key"
+        entity._source_object = "obj"
+        entity.signature = "sig"
+        mock_verify.return_value = False
+        with pytest.raises(SignatureVerificationError):
+            entity._validate_signatures()
+            mock_verify.assert_called_once_with("key", "obj", "sig")
+        mock_verify.reset_mock()
+        mock_verify.return_value = True
+        entity._validate_signatures()
+        mock_verify.assert_called_once_with("key", "obj", "sig")
diff --git a/federation/tests/entities/diaspora/test_mappers.py b/federation/tests/entities/diaspora/test_mappers.py
index 3024a39..04636a6 100644
--- a/federation/tests/entities/diaspora/test_mappers.py
+++ b/federation/tests/entities/diaspora/test_mappers.py
@@ -1,5 +1,5 @@
 from datetime import datetime
-from unittest.mock import patch
+from unittest.mock import patch, Mock
 
 import pytest
 
@@ -89,7 +89,7 @@ class TestDiasporaEntityMappersReceive(object):
         assert comment.signature == "((signature))"
         mock_validate.assert_called_once_with()
 
-    @patch("federation.entities.diaspora.mappers.DiasporaComment._validate_signatures")
+    @patch("federation.entities.diaspora.mappers.DiasporaLike._validate_signatures")
     def test_message_to_objects_like(self, mock_validate):
         entities = message_to_objects(DIASPORA_POST_LIKE)
         assert len(entities) == 1
@@ -158,6 +158,18 @@ class TestDiasporaEntityMappersReceive(object):
         entities = message_to_objects(DIASPORA_POST_SIMPLE)
         assert entities[0]._source_protocol == "diaspora"
 
+    @patch("federation.entities.diaspora.mappers.DiasporaComment._validate_signatures")
+    def test_element_to_objects_calls_sender_key_fetcher(self, mock_validate):
+        mock_fetcher = Mock()
+        message_to_objects(DIASPORA_POST_COMMENT, mock_fetcher)
+        mock_fetcher.assert_called_once_with("alice@alice.diaspora.example.org")
+
+    @patch("federation.entities.diaspora.mappers.DiasporaComment._validate_signatures")
+    @patch("federation.entities.diaspora.mappers.retrieve_and_parse_profile")
+    def test_element_to_objects_calls_retrieve_remote_profile(self, mock_retrieve, mock_validate):
+        message_to_objects(DIASPORA_POST_COMMENT)
+        mock_retrieve.assert_called_once_with("alice@alice.diaspora.example.org")
+
 
 class TestGetOutboundEntity(object):
     def test_already_fine_entities_are_returned_as_is(self):