diff --git a/requirements.txt b/requirements.txt
index 0108c5621..42910d1be 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -11,5 +11,5 @@ ujson>=1.35
 dill>=0.2,<0.3
 requests>=2.13.0,<3.0.0
 regex==2017.4.5
-ftfy==4.4.2
+ftfy>=4.4.2,<5.0.0
 pytest>=3.0.6,<4.0.0