use strict;
use warnings;

while( my $bates_number = <DATA> )
{
    chomp $bates_number;

    if( $bates_number =~ m/^( XYZ \s \d{2,3} (?:\sST)? ) \s ( \d{8}   )$/x  ||
        $bates_number =~ m/^( XYZ \s [UV] \s \d{1,3}   ) \s ( \d{8}   )$/x  ||
        $bates_number =~ m/^( XYZ \s \d{3}             )    ( \d{8}   )$/x  ||
        $bates_number =~ m/^( XYZ                      ) \s ( \d{7,8} )$/x  ||
        $bates_number =~ m/^( ABC-M-                   )    ( \d{7}   )$/x  ||
        $bates_number =~ m/^( ABCD-                    )    ( \d{8}   )$/x  ||
        $bates_number =~ m/^(                          )    ( \d{11}  )$/x    )

    {
        # my ( $pfx, $num ) = ( $1, $2 ); # could assign here
        printf( "%-20s  %-12s  % d\n", $bates_number, $1, $2 );
    }
    else
    {
        print "Invalid Bates number: $bates_number\n";
    }
}

__DATA__
XYZ 123 00654321
XYZ 12 ST 00123456
XYZ 123 ST 00654321
XYZ U 123 00123456
XYZ U 12 00654321
XYZ V 1 00123456
XYZ 12300654321
XYZ 00123456
XYZ 0654321
ABC-M-0123456
ABCD-00654321
00000123456

##</code><code>##

XYZ 123 00654321      XYZ 123        654321
XYZ 12 ST 00123456    XYZ 12 ST      123456
XYZ 123 ST 00654321   XYZ 123 ST     654321
XYZ U 123 00123456    XYZ U 123      123456
XYZ U 12 00654321     XYZ U 12       654321
XYZ V 1 00123456      XYZ V 1        123456
XYZ 12300654321       XYZ 123        654321
XYZ 00123456          XYZ            123456
XYZ 0654321           XYZ            654321
ABC-M-0123456         ABC-M-         123456
ABCD-00654321         ABCD-          654321
00000123456                          123456