diff --git a/COPYING.EXCEPTION b/COPYING.EXCEPTION
new file mode 100644
index 0000000..8ef8f44
--- /dev/null
+++ b/COPYING.EXCEPTION
@@ -0,0 +1,3 @@
+LICENSE EXCEPTION
+
+In addition, as a special exception, the output, including source code, that this program generates, is not governed by this license. That is, anyone using this program is free to license its output, together with his or her program that the output is linked with, according to his or her own will. This is true, even though this program copies significant parts of its source code files to its output.