I need to remove all unique entries from a list of lists such that all lists are the same.

From what you have done, it seems to me like you want to get the elements which exist in all lists.

I can't suggest a better way, but it can be shorter be removing unnecessary code.

use strict;
use warnings;
use Data::Dumper;

my $temp = ... # your list of lists here

my $numterms = @$temp;
my $seen = {};
for my $term (@$temp)
{
    map { $seen->{$_}++ } @$term;
}
my @results = grep {$seen->{$_} == $numterms} keys %$seen;
print STDERR Data::Dumper->Dump([\@results]);
[download]

/prakash