--- grep-2.21/build-aux/update-copyright.orig 2015-08-02 18:10:29.174256966 +0100
+++ grep-2.21/build-aux/update-copyright 2015-08-02 18:11:19.926287054 +0100
@@ -124,7 +124,7 @@
use warnings;
my $copyright_re = 'Copyright';
-my $circle_c_re = '(?:\([cC]\)|@copyright{}|©)';
+my $circle_c_re = '(?:\([cC]\)|@copyright\{}|\\\\\(co|©)';
my $holder = $ENV{UPDATE_COPYRIGHT_HOLDER};
$holder ||= 'Free Software Foundation, Inc.';
my $prefix_max = 5;