diff --git a/changelog.d/6805.misc b/changelog.d/6805.misc
new file mode 100644
index 0000000000..08aa80bcd9
--- /dev/null
+++ b/changelog.d/6805.misc
@@ -0,0 +1 @@
+Refactoring work in preparation for changing the event redaction algorithm.
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index 8eddb3bf2c..9562faa3ee 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -410,7 +410,7 @@ class FederationServer(FederationBase):
         origin_host, _ = parse_server_name(origin)
         await self.check_server_matches_acl(origin_host, pdu.room_id)
         pdu = await self._check_sigs_and_hash(room_version, pdu)
-        ret_pdu = await self.handler.on_invite_request(origin, pdu)
+        ret_pdu = await self.handler.on_invite_request(origin, pdu, room_version)
         time_now = self._clock.time_msec()
         return {"event": ret_pdu.get_pdu_json(time_now)}
 
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index ca484e5458..01372f6d47 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -1482,13 +1482,13 @@ class FederationHandler(BaseHandler):
         return {"state": list(state.values()), "auth_chain": auth_chain}
 
     @defer.inlineCallbacks
-    def on_invite_request(self, origin, pdu):
+    def on_invite_request(
+        self, origin: str, event: EventBase, room_version: RoomVersion
+    ):
         """ We've got an invite event. Process and persist it. Sign it.
 
         Respond with the now signed event.
         """
-        event = pdu
-
         if event.state_key is None:
             raise SynapseError(400, "The invite event did not have a state key")