diff --git a/engine/common/zone.c b/engine/common/zone.c
index 98af81eb..0e082858 100644
--- a/engine/common/zone.c
+++ b/engine/common/zone.c
@@ -1,6 +1,9 @@
 /*
 zone.c - zone memory allocation from DarkPlaces
+Copyright (C) 1996-1997 Id Software, Inc.
+Copyright (C) 2000-2007 DarkPlaces contributors
 Copyright (C) 2007 Uncle Mike
+Copyright (C) 2015-2023 Xash3D FWGS contributors
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by