April 4 (Bloomberg) -- Google Inc., Microsoft Corp., Yahoo! Inc. and other Internet search-engine providers must cut the time they retain users' online records to comply with European Union privacy laws, advisers to regulators decided today.

Privacy-protection officials from the 27 EU nations unanimously adopted proposals that may force search engines to change the way they store data unless there is ``a valid justification.'' The Article 29 Data Protection Working Party decided after a two-day meeting in Brussels today that the maximum time for keeping search data is six months.

Today's decision may threaten ``the golden goose'' of the broader business of Internet advertising, which uses customers' online records to offer personally targeted ads, Greg Sterling, an analyst at Sterling Market Intelligence in San Francisco, said in a telephone interview.

Alex Tuerk, the group's chairman, said today that search engines must delete personal information ``the moment they don't need it.'' Sterling said the six-month period sounded reasonable.

Google rose $15.97 to $471.09 at 4 p.m. New York time in Nasdaq Stock Market trading. The stock has dropped 32 percent this year, compared with a 6.7 percent decline in the Standard & Poor's 500 Information Technology Index.

In May 2007, the group told Google, owner of the world's most popular search engine, that it may be violating EU privacy laws by preserving user data for as long as two years. That spurred Google to trim the storage period to 18 months. Microsoft and Yahoo followed in July, saying they would limit the time they keep data records to 18 months and 13 months, respectively.

Google's Stance

Google, based in Mountain View, California, today said that it's committed to working with privacy officials to ``explore ways to improve privacy online for all users.''

Google billed itself as the first search company to make logs anonymous and to cut the life of ``cookies'' used to track Internet users' activity.

``Our desire to extend privacy protections on the Internet around the world motivates our work for global privacy standards,'' the company said in an e-mailed statement.

Microsoft is looking forward to reviewing the EU group's recommendations ``as part of our continued work with them on this important issue,'' said Thomas Myrup Kristensen, a spokesman for the Redmond, Washington-based company. ``We believe that it is important to implement a range of privacy protections for search.''

Yahoo, based in Sunnyvale, California, is reviewing the group's opinion, said Andrew Cecil, director of public policy at Yahoo! Europe.

Tuerk, who is also France's data protection president, took over from Germany's Peter Schaar as chairman of the Article 29 group on Feb. 19. The group is made up of the 27 EU nations and an additional three non-EU countries, including Norway.

``This report will influence the way national authorities across Europe will act against search engines in the future,'' Tuerk said.

To contact the reporter on this story: Stephanie Bodoni in Luxembourg at sbodoni@bloomberg.net

Last Updated: April 4, 2008 16:13 EDT