diff --git a/requirements.txt b/requirements.txt
index 6c701be..f3f606a 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,6 +6,6 @@ pbr>=0.6,!=0.7,<1.0
 pep8==1.5.7
 pyflakes==0.8.1
 flake8==2.2.4
-mccabe==0.2.1
+mccabe==0.2.1 # MIT License
 
 six>=1.7.0