diff --git a/README.md b/README.md
index fe7969f..80bb0fa 100644
--- a/README.md
+++ b/README.md
@@ -713,7 +713,7 @@ From the included project metadata:
 
 ## License
 
-The source tree includes a root-level `COPYING` file with the GPL-2 license text. Source files carry GPL-2-or-later headers and preserve the original Martin Stover attribution for the historical mars_nwe utility code, with current maintenance attribution where appropriate.
+The source tree includes a root-level `COPYING` file with the GPL-2 license text. Source files carry `GPL-2.0-only` headers and preserve the original Martin Stover attribution for the historical mars_nwe utility code, with current maintenance attribution where appropriate.
 
 
 Debug/test helpers: