Do you only want to see the counts? I guess not, you also want to see the number and colour to which the count belongs.

BTW, the main point of $_ is you don't have to write it. If there's no assingment in a my statement, there's no need to undef it. 

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

my %hash;
<DATA>; # Skip the header.
while (<DATA>) {
    my ($name, $number, $color) = split;
    $hash{$name}{$number}{$color}++;
}

my %returnedHash = %{ $hash{GNAEUS} };

for my $number (keys %returnedHash) {
    for my $color (keys %{ $returnedHash{$number} }) {
        print "$number $color $returnedHash{$number}{$color}\n";
    }
}
__DATA__
NAME NUMBER COLOR
GNAEUS 1 BLUE
GNAEUS 1 RED
GNAEUS 3 MAGENTA
GNAEUS 3 GREEN
GNAEUS 3 GREEN
FABIUS 1 BLUE
FABIUS 2 YELLOW
FABIUS 1 RED

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لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: Grep hash of hashes by choroba
in thread Grep hash of hashes by pimperator

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