use strict;

# will use this variable to hold third
# column value of the last record.
my $last_val;
while(<DATA>) {
  chomp;
  next unless (m/.*<tab>.*<tab>\s*(\d{2,})/);
  # third column value has changed?
  print "\n" unless ($last_val == $1); # yes, skip to next line
  print;
  $last_val = $1;
}

__DATA__
0<tab>761<tab>94 (041352) 
0<tab>2311<tab> 94 (0.00) 
0<tab>27<tab> 94 (NG012) 
0<tab>892<tab>94 (04/23/2002) 
0<tab>494<tab> 94 (520-004) 
1<tab>343<tab> 38 (info)
1<tab>133<tab> 38 (info)
1<tab>345<tab> 94 (info)