diff --git a/fastapi/dependencies/utils.py b/fastapi/dependencies/utils.py
index 6732a1876..3288592c7 100644
--- a/fastapi/dependencies/utils.py
+++ b/fastapi/dependencies/utils.py
@@ -158,12 +158,12 @@ def get_flat_dependant(
         body_params=dependant.body_params.copy(),
         name=dependant.name,
         call=dependant.call,
-        request_param_name=dependant.request_param_name,
-        websocket_param_name=dependant.websocket_param_name,
-        http_connection_param_name=dependant.http_connection_param_name,
-        response_param_name=dependant.response_param_name,
-        background_tasks_param_name=dependant.background_tasks_param_name,
-        security_scopes_param_name=dependant.security_scopes_param_name,
+        request_param_names=dependant.request_param_names.copy(),
+        websocket_param_names=dependant.websocket_param_names.copy(),
+        http_connection_param_names=dependant.http_connection_param_names.copy(),
+        response_param_names=dependant.response_param_names.copy(),
+        background_tasks_param_names=dependant.background_tasks_param_names.copy(),
+        security_scopes_param_names=dependant.security_scopes_param_names.copy(),
         own_oauth_scopes=dependant.own_oauth_scopes,
         parent_oauth_scopes=use_parent_oauth_scopes,
         use_cache=dependant.use_cache,