diff --git a/Casks/vox-legacy.rb b/Casks/vox-legacy.rb
index 41049822d..17f32a6e9 100644
--- a/Casks/vox-legacy.rb
+++ b/Casks/vox-legacy.rb
@@ -4,6 +4,7 @@ class VoxLegacy < Cask
 
   url "http://cloud.coppertino.com/vox/Vox_#{version}.dmg"
   homepage 'http://coppertino.com/vox/'
+  license :unknown
 
   app 'Vox.app'
 end