and the question is what?

Maybe what you need is a test to see if the hash entries exist? The following may help:

#!/sbcimp/perl/bin/perl
use strict;
use warnings;

my %extend_hash = (
    '6' => {
        'IACI'     => {'ARCX' => {'specialist' => '1', 'penny' => '0'}
+},
        'MCHP'     => {'ARCX' => {'specialist' => '1', 'penny' => '0'}
+},
        'BC'       => {'AMXO' => {'specialist' => '1', 'penny' => '0'}
+},
        'WINN'     => {'XISX' => {'specialist' => '1', 'penny' => '0'}
+},
        'WTR_S5F4' => {'XISX' => {'specialist' => '1', 'penny' => '0'}
+},
        'XLY'      => {'CS'   => {'specialist' => '0', 'penny' => '1'}
+}
        }
        );
my %spec_hash = (
    'XISX' => {
        'FCEL' => 1, 'GPS'  => 1, 'MCO'  => 1, 'DPZ'  => 1,
        'ENTG' => 1, 'PDS'  => 1
    }
);

foreach my $symbol (sort keys %{$extend_hash{6}}) {
    foreach my $exch (sort keys %{$extend_hash{6}{$symbol}}) {
        next if !$extend_hash{6}{$symbol}{$exch}{'specialist'};
        next
            if !exists $spec_hash{$exch}{$symbol}
            || $spec_hash{$exch}{$symbol} == 1;
        print "$symbol = '$exch'\n";
    }
}
[download]

If that doesn't do it for you, you need to actually ask a question and provide a run-able code sample. See I know what I mean. Why don't you? for some hints.