use strict;
my $str = 'Buxtehude /1234 KundenAuftragEinsatzart1 698874/6387/01
KundenAuftragEinsatzart 698874/6387
Musterstadt /1234 KundenAuftragEinsatzart2 698874/6387/01
KundenAuftragEinsatzart3 698874/6387/01
KundenAuftragEinsatzart4 698874/6387/01';
my $regex = qr/\S+\s\d+\/\d+\/\d+/mp;
my $subst = '';
my $result = $str =~ s/$regex/$subst/rg;
print "The result of the substitution is' $result\n";
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html