As you will see, the actual webpages contain four different document numbers (COM (2000) 862, COM (2000) 847, COM (2000) 844, COM (2000) 840) whereas the program always delivers the same one (COM (2000) 862), which is the one of the first webpage accessed.

Presumably, this is due to an internal storage variable of the GET routine, which is appended and not replaced each time a new GET request is processed.

#! C:/programme/perl
use LWP::Simple;
use LWP::UserAgent; 
use HTML::Stripper;
use warnings;
use strict;
our $stripper = HTML::Stripper->new( skip_cdata => 1, strip_ws => 1 );
our $ID;
our @ID=(161060, 160920, 160999, 160899);
our $count=1;
foreach $ID (@ID) {
 my $content;
 my $content_full;
 my $url="http://europa.eu.int/prelex/detail_dossier_real.cfm?CL=en&Do
+sId="."$ID";
 $content_full=" ";
 $content_full=get($url);
 $content=$stripper->strip_html($content_full);
 our $i_type=index($content, " COM ");
 our $d_type=substr($content, $i_type+1,3);
 our $d_year=substr($content, $i_type+6,4);
 our $d_number=substr($content, $i_type+12,3);
 our $proposal="$d_type "."\($d_year\)"." $d_number";
 print "Proposal\: $proposal \n";
 open DB, ">> C:/programme/perl/test/prelex.dta" 
  or  die "Problem: $!";
 flock (DB, 2);
 print  DB "$proposal\n";
 close DB;
}
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You are re-using the $stripper object. It accumulates data. Nothing to do with hidden variables in get()

Entia non sunt multiplicanda.
   -- William of Occam