diff --git a/pkgs/tools/X11/ratmen/default.nix b/pkgs/tools/X11/ratmen/default.nix
index c438381d7125..19e5fe69da5b 100644
--- a/pkgs/tools/X11/ratmen/default.nix
+++ b/pkgs/tools/X11/ratmen/default.nix
@@ -25,7 +25,7 @@ stdenv.mkDerivation {
   meta = {
     inherit (s) version;
     description = ''A minimalistic X11 menu creator'';
-    license = stdenv.lib.licenses.free ;
+    license = stdenv.lib.licenses.free ; # 9menu derivative with 9menu license
     maintainers = [stdenv.lib.maintainers.raskin];
     platforms = stdenv.lib.platforms.linux;
     homepage = "http://www.update.uu.se/~zrajm/programs/";