Untested: 
$/ = "";
while (<>) {
    my ($l1, $l2) = split /\n/;
    $l1 =~ /=/p; my $a1 = ${^POSTMATCH};
    $l2 =~ /=/p; my $a2 = ${^POSTMATCH};
    next if $a1 eq $a2;
    print;
}

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In reply to Re: extracting dissimilar lines by JavaFan
in thread extracting dissimilar lines by anasuya

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