diff --git a/util/merge_copyrights b/util/merge_copyrights
index 1f2b64bf28..92619e1b7a 100644
--- a/util/merge_copyrights
+++ b/util/merge_copyrights
@@ -35,7 +35,8 @@ while (<CHANGES>) {
 	       /CVS/ |		# CVS directory
 	       /\.git/ |		# git directory
 	       /\.gitignore |   # .gitignore files
-	       /Makefile.in |   # build system doesn't need to have copyright
+	       Makefile.in  |   # build system doesn't need to have copyright
+	       /m4/ |           # build system doesn't need to have copyright
 	       /configure   |   # build system doesn't need to have copyright
 	       /fuzz/.*\.in/ |  # ignore fuzz corpus
 	       util/newcopyrights | # our output