diff --git a/tests_requirements.txt b/tests_requirements.txt
index a5d0566..f02d009 100644
--- a/tests_requirements.txt
+++ b/tests_requirements.txt
@@ -1,5 +1,5 @@
 eventlet
-mock==1.1.2
+mock
 nose>=0.10.4
 nosexcover
 flake8