I'm currently persuing Evesham Micros after they spammed a scraped email address. As part of this I emailed the Data Protection Registrar to see what legal action I could take.

Part of the DPR's reply included a document template which you can use to attempt to force "opt out" or deletion. The response from the DPR included the following paragraphs;

The First Data Protection Principle requires, amongst other things, that personal data shall be processed fairly. The Information Commissioner considers that where unsolicited marketing material continues to be sent to someone who has requested suppression of his or her email address, this requirement may have been breached.

If you are seeking to prevent the use of your data for direct marketing (including emails) you may be interested to know that Section 11 of the Act states that, "an individual is entitled at any time, by notice in writing to a data controller, to require the data controller at the end of such period as is reasonable in the circumstances to cease, or not to begin, processing for the purposes of direct marketing personal data in respect of which he is the data subject." Therefore I would suggest that you write to the companies concerned, stating that, under S.11 of the Data Protection Act 1998, you wish them to cease processing your personal data for the purposes of direct marketing.

There is no specific wording needed for a section 11 notice, however I have included with this e-mail a draft copy of such a notice, which you may wish to copy and send to the organisation concerned.

If they do not comply then you can push the DPR for action.

You can download the template as a word document or a pdf.

I am still waiting to see exactly what the ASA will do, as under their new guidelines spamming is not permitted. I don't hold out much hope, self regulation never works well.