Well, let me 1st say something about speed. This thing is gonna be slow. Perhaps you could try something like this:

my %match;
if (open (FH1, "first.txt"))
{
  while (<FH1>)
  {
    if (/^\s+(\S+)/)
    {
      $match{$1} = 1;
      print "Found $1\n";
    }
  }
  close (FH1);
}
if (open (FH2, "data.txt"))
{
  while (<FH2>)
  {
    if (/^\s+\S+\s+\S+\s+(\S+)/)
    {
      if ($match{$1})
      {
         print "Match on $1\n";
      }
      else
      {
         print "NO match on $1\n";
      }
    }
  }
  close (FH2);
}
[download]

code is untested.