The European Commission's working group on data protection has warned members of the online advertising industry that their current approach does not comply with Europe's ePrivacy laws.

The Article 29 Working Party (A29 WP) said in a letter published Tuesday that voluntary plans drawn up by Europe's digital advertising industry representatives, the European Advertising Standards Alliance (EASA) and IAB Europe, do not meet the consent and information requirements of the recently revised ePrivacy Directive.

The advertising representatives favor an icon-based approach along with links to a website www.youronlinechoices.eu to inform Internet users of their rights. Users could click on an icon placed beside any behaviorally-targeted advertisement to find out how the ad was generated. But the A29 WP wants a Web browser-based Do Not Track (DNT) protocol.

Implementing the ePrivacy Directive has proved a headache for many European Union countries. It became law in May 2011, but some member states are still struggling to put into force the rule that requires "explicit consent" from Internet users before storing their data or installing cookies on their computers. Even the Digital Agenda Commissioner Neelie Kroes admitted that applying the law in practice is not easy.

"There are different interpretations, sometimes, or even confusion about what the rules mean and how to comply with them. The industry has set up a self-regulatory initiative on online behavioral advertising. However this code alone, while certainly contributing to transparency, will not solve the issue, being inherently limited," she said last month.

A29 WP chairman Jacob Kohnstamm indicated in his letter that he agrees with the Commissioner, accepting that while an icon may help raise awareness, it does not go far enough. "A DNT-setting in a browser means that users should no longer be tracked, instead of just not being shown targeted advertisements," he said.

DNT standards, based partly on work done by the W3C, are due to be adopted in June and the A29 WP urged the online advertising industry "to constructively contribute" towards drawing up a DNT protocol.

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