$ cat flog.pl
#!/usr/bin/env perl
use strict;
use warnings;

my $o = bless {a=>1,b=>2,c=>3}, 'Flog';

my $j = {
   J => { %$o }, # Make a copy of the object
   K => $o       # or just pass it in
};

print "Before:\n";
dumpit($j);

$j->{J}{a}=7;
$j->{K}{b}=8;
$o->{c}=9;

print "After:\n";
dumpit($j);

sub dumpit {
    my $t = shift;
    for my $k ('a' .. 'c') {
        print "$k : $t->{J}{$k} : $t->{K}{$k} : $o->{$k}\n";
    }
}
Roboticus@Waubli ~
$ perl flog.pl
Before:
a : 1 : 1 : 1
b : 2 : 2 : 2
c : 3 : 3 : 3
After:
a : 7 : 1 : 1
b : 2 : 8 : 8
c : 3 : 9 : 9