use warnings;
my $copyright_re = 'Copyright';
-my $circle_c_re = '(?:\([cC]\)|@copyright{}|\\\\\(co|©)';
+my $circle_c_re = '(?:\([cC]\)|@copyright\{}|\\\\\(co|©)';
my $holder = $ENV{UPDATE_COPYRIGHT_HOLDER};
$holder ||= 'Free Software Foundation, Inc.';
my $prefix_max = 5;