An influential EC policy group, the Article 29 Working Party, is calling on search engines to delete users' cookies within six months - a much shorter period than that typically used by Google, MSN, and Yahoo!
Google volunteered to anonymise information held after 18 to 24 months following earlier EC concerns. After further negotiations with Article 29 this was lowered to 18 months. So the information was still kept but it did not include anything that could identify individuals.
Article 29 is made up of privacy regulators from member states - the UK is represented by Information Commissioner Richard Thomas. The review of search engines comes from an article, in English, on the Dutch Data Protection Authority website following the group's meeting in Brussels last week.
Although the group's advice is not binding it is likely to be broadly adopted by the European Commission.
The Working Party finds that search engines are covered by the Data Protection Directive. They must delete or anonymise personal data "once they are no longer necessary for the purpose for which they were collected". Search engines must also inform users of any third party use of their data.
The Working Party also warns that any "enrichment" of user profiles, with data not provided by the users, needs those users' consent.
Google says it keeps the information in order to improve search results - by identifying what you have previously searched for it can do a better job of fine-tuning future search results. It is also, of course, useful for targeting advertising.
On its public policy blog Google repeated the importance of data logs to improving its search service claiming that: "Today, a Google search is far more likely to provide you with the information you're looking for that it did a few years ago."
The search giant also disagreed with the policy group's view that IP addresses should be treated as personal information. Google blogged: "Based on our own analysis, we believe that whether or not an IP address is personal data depends on how the data is being used.".
Google wants the benefits of data warehousing - improvements in services - to be included in discussions of user privacy. ®