diff --git a/Casks/ivolume.rb b/Casks/ivolume.rb
index a6bd0951d22..1b1a8d02413 100644
--- a/Casks/ivolume.rb
+++ b/Casks/ivolume.rb
@@ -4,7 +4,7 @@ cask :v1 => 'ivolume' do
 
   url 'http://www.mani.de/download/ivolume/iVolume3Mac.dmg'
   homepage 'http://www.mani.de/en/ivolume/'
-  license :unknown
+  license :unknown    # todo: improve this machine-generated value
 
   app 'iVolume.app'
 end