diff --git a/setup.py b/setup.py
index 34bf4685d5dd5..4b2e8c6e01889 100755
--- a/setup.py
+++ b/setup.py
@@ -274,7 +274,7 @@ def initialize_options(self):
         ujson_lib = pjoin(base,'ujson','lib')
         self._clean_exclude = [pjoin(dt,'np_datetime.c'),
                                pjoin(dt,'np_datetime_strings.c'),
-                               pjoin(src,'period.c'),
+                               pjoin(src,'period_helper.c'),
                                pjoin(parser,'tokenizer.c'),
                                pjoin(parser,'io.c'),
                                pjoin(ujson_python,'ujson.c'),