diff --git a/requirements.txt b/requirements.txt
index 4b4ec6d..da57c39 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -14,4 +14,4 @@ Flask-OAuthlib==0.9.3
 dnspython>=1.12.0
 python-saml==2.3.0
 pyOpenSSL>=0.15
-pytz=>2017.3
+pytz>=2017.3