use strict;

my $title;

while ( <DATA> )
{
    $title = $_ if /^Title: .+$/;
    print $title, $_ if /^856   invalid/;
}

close IN;

__DATA__
Title:  Mary moo-cow 
856   invalid url

Title:  the mechanics 
856  valid url

Title:  Terminator 2
856   invalid url
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