Google will remove all search queries after 18 to 24 months

IIn a nod to privacy advocates, Google com. said Wednesday that they will adopting a new data retention policy so that it's harder to link users to what they search for online. Under the plan, the Mountain View Internet company will shroud the information it collects about users in anonymity, eliminating a potential treasure trove of evidence for government search warrants and subsistances.

By the end of 2007, Google expects to purge important identifying information on its computer servers about the sources of virtually all search queries after 18 to 24 months.

Subsequently, the company will have access to only partial records, so that no one can trace the queries back to individual users.

Google's move is intended to comply with various foreign laws and proposed legislation dictating that Web sites must keep user information for up to two years in case it is needed for legal proceedings. Similar rules are under consideration in the United States.

Google is the first major search engine to set a time limit for retention of search information, which can reveal a great deal about an individual such as whether they're sick (as indicated by a number of queries about cancer) and political affiliation (demonstrated by searches for certain blogs).

Until now, the company kept search logs indefinitely, raising criticism that the data could be misused by Google, law enforcement or marketers. Google said the changes are in response to feedback from privacy groups and government agencies, including the Norwegian Data Protection Authority, which raised concerns about Google's existing practices. The new policy, Google said, provides more transparency to users about data retention and better protects their privacy.

Kurt Opsahl, an attorney for the Electronic Frontier Foundation, a digital rights group, gave measured praise to Google's decision, calling it a step in the right direction.

He asked that Google similarly purge information collected about users of its other products, such as YouTube. Retention of search records emerged as a hot-button issue last year after a demand by the Justice Department that several Web sites turn over query data became public.

Yahoo Inc., Time Warner's AOL and Microsoft Corp. handed over the information, to the consternation of many privacy advocates, but Google fought the request in court and ultimately got the amount it had to provide reduced.

Separately, AOL made a high-profile blunder by posting 19 million search queries online as part of a research project. Ostensibly anonymous, the information was used to identify some of the users responsible for the queries, prompting a public apology by the Web site and a series of resignations.

"By taking some technical measures to anonymize this data, there is an extra layer of protection," Opsahl said. "You can't disclose what you don't have."

As part of the new policy, Google will erase eight of the bits that make up an Internet Protocol address, known commonly as an IP address, that identifies the computer used to make a search query. It will also make cookies -- the small files that help track user visits to specific Web sites and preferences -- anonymous.

After the plan is implemented, Google intends to keep the partial records and associated search query terms, explaining that the information will help the company improve its services and help detect fraud.