diff --git a/src/lib9/fmt/nan64.c b/src/lib9/fmt/nan64.c
index 9c0cc7bf..d408695d 100644
--- a/src/lib9/fmt/nan64.c
+++ b/src/lib9/fmt/nan64.c
@@ -1,3 +1,5 @@
+/* Copyright (c) 2002-2006 Lucent Technologies; see LICENSE */
+
 /*
  * 64-bit IEEE not-a-number routines.
  * This is big/little-endian portable assuming that