diff --git a/docs/requirements.txt b/docs/requirements.txt
index d825a5fcc..7611ea463 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,7 +1,7 @@
 # requirements for working on docs
 
 # install pillow from master if you're into that, but RtD needs this
-pillow>=2.2.1
+pillow>=2.4.0
 
 Jinja2==2.7.1
 MarkupSafe==0.18