diff --git a/stdlib/subprocess.pyi b/stdlib/subprocess.pyi
index 98bbf7d33f90..cb8ce4c0db3b 100644
--- a/stdlib/subprocess.pyi
+++ b/stdlib/subprocess.pyi
@@ -118,6 +118,12 @@ else:
 
 _T = TypeVar("_T")
 
+# These two are private but documented
+if sys.version_info >= (3, 11):
+    _USE_VFORK: bool
+if sys.version_info >= (3, 8):
+    _USE_POSIX_SPAWN: bool
+
 class CompletedProcess(Generic[_T]):
     # morally: _CMD
     args: Any