The !~ binding returns true for non-matches, 

$reference = ''
    if $reference !~ m/38[0-9]{8}[A-Z]{3}/;

[download]
or to keep the important part first and the match positive, 
$reference =~ m/38[0-9]{8}[A-Z]{3}/
    or $reference = '';

[download]

After Compline,
Zaxo

In reply to Re: Regex 'If Not Match' by Zaxo
in thread Regex 'If Not Match' by PugSA

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