Data leak prevention for Danish social security numbers (regular expression)
I've created a regular expression to prevent leaking Danish social security numbers via e-mails. I use this filter in my SPAM filter/SMTP (outgoing and incoming) server (SpamTitan) and it will match both 123456-7890 and 1234567890: (\W|^)[0-9][0-9][0-9][0-9][0-9][0-9](-| |)[0-9][0-9][0-9][0-9](\W|$)