diff --git a/pkgs/development/libraries/cmark/default.nix b/pkgs/development/libraries/cmark/default.nix
index 81df7e86319..fce02dac950 100644
--- a/pkgs/development/libraries/cmark/default.nix
+++ b/pkgs/development/libraries/cmark/default.nix
@@ -23,5 +23,6 @@ stdenv.mkDerivation rec {
     homepage = https://github.com/jgm/cmark;
     maintainers = [ maintainers.michelk ];
     platforms = platforms.unix;
+    license = licenses.bsd2;
   };
 }