diff --git a/proto-stubs/message.pyi b/proto-stubs/message.pyi
index 8864655..94f30fb 100644
--- a/proto-stubs/message.pyi
+++ b/proto-stubs/message.pyi
@@ -46,6 +46,8 @@ class MessageMeta(type):
     ) -> None: ...
 
 class Message(metaclass=MessageMeta):
+    _pb: message.Message
+
     def __init__(
         self: _M,
         mapping: _M | Mapping | message.Message | None = ...,