my %largest;

while (<>) {
   my ($item, $group_id, $count) = split;

   next if $largest{$group_id}
        && $largest{$group_id}[2] >= $count;

   $largest{$group_id} = [ $item, $group_id, $count, $_ ];
}

for (values(%largest)) {
   print($_->[-1]);
}

[download]

Keeps first on ties.

Update: Added note at bottom.

In reply to Re: Retrieving data with largest count by ikegami
in thread Retrieving data with largest count by Angharad

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