diff --git a/synapse/app/generic_worker.py b/synapse/app/generic_worker.py
index 561a6f4b22..d596852419 100644
--- a/synapse/app/generic_worker.py
+++ b/synapse/app/generic_worker.py
@@ -676,8 +676,9 @@ class GenericWorkerReplicationHandler(ReplicationClientHandler):
             elif stream_name == "device_lists":
                 all_room_ids = set()
                 for row in rows:
-                    room_ids = await self.store.get_rooms_for_user(row.user_id)
-                    all_room_ids.update(room_ids)
+                    if row.entity.startswith("@"):
+                        room_ids = await self.store.get_rooms_for_user(row.entity)
+                        all_room_ids.update(room_ids)
                 self.notifier.on_new_event("device_list_key", token, rooms=all_room_ids)
             elif stream_name == "presence":
                 await self.presence_handler.process_replication_rows(token, rows)