There is a caveat to this... if the link is a redirect from javascript (see below) the referrer is blank. Also, If you are using this to validate the referrer as an authorized link and you are creating links in emails, you have to allow them through.

Hope this helps.

 

<script>

document.location.href = 'http:.....foo@foobar.fwx'

</script>

referrer is empty.