diff --git a/pkgs/tools/graphics/welkin/default.nix b/pkgs/tools/graphics/welkin/default.nix
index 111abc745be5..e825f5e5d2b8 100644
--- a/pkgs/tools/graphics/welkin/default.nix
+++ b/pkgs/tools/graphics/welkin/default.nix
@@ -32,7 +32,7 @@ stdenv.mkDerivation rec {
     ];
     hydraPlatforms = [];
     sourceProvenance = with lib.sourceTypes; [ binaryBytecode ];
-    license = lib.licenses.free;
+    license = lib.licenses.bsd3;
     platforms = with lib.platforms; unix;
   };
 }