diff --git a/requirements.txt b/requirements.txt
index 30f7322b..fdc5cc08 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
 mock==1.0.1
 requests==1.2.3
-six==1.3.0
+six>=1.3.0
 websocket-client==0.11.0