By VAUHINI VARA
November 21, 2007; Page D8
Some users of the Facebook Inc. Web site have been startled by a new feature that tracks their activity outside of the site and shows it to their friends -- renewing questions about the privacy implications of a growing practice of exploiting personal information in online advertising.
The social-networking service earlier this month began posting updates about users' activities on Web sites outside of Facebook and on commercial pages within Facebook -- in some cases, alongside ads from the companies behind those Web sites or pages. Facebook is posting users' photos alongside certain advertisements, another feature that has alarmed some privacy advocates and users.
For instance, a user who logs on to Facebook might see an update in a section of the site called the "news feed" noting the movie a friend rented from an online site, along with a photo of that friend and a movie-rental ad.
MoveOn.org Civic Action, a media-watchdog group, created a group on the Facebook site yesterday called, "Petition: Facebook, stop invading my privacy!" By last night, nearly 2,000 Facebook members had joined the group.
The backlash comes as online advertisers experiment with "behavioral targeting," or sending people ads based on personal information about them. A common type of behavioral targeting involves tracking the Web sites an Internet user visits in order to send them ads that are relevant to their interests.
Facebook, critics argue, takes its advertising beyond that by collecting specific data about its users' activities on outside sites and broadcasting that data to their friends and acquaintances. Critics of the new feature say the Palo Alto, Calif., company makes it difficult to opt out of it.
Users can't opt out of the program, called "Facebook Beacon," altogether. Instead, they have to opt out on a case-by-case basis when they use one of the outside sites.
Chris Kelly, chief privacy officer of Facebook, said Facebook is transparent in communicating to users what it is tracking. When a user visits an outside site and completes an action like buying a movie ticket, a box shows up in the corner of his Internet browser telling that person the outside Web site is sending that information to Facebook. The user can opt out by clicking on text that reads "No, thanks." If the user doesn't, the next time they visit Facebook, the user will see a message from Facebook asking for permission to show the information to their friends. If the user declines, the information won't be sent.
Mr. Kelly said Facebook welcomes feedback and could change its settings and policies for advertising and privacy based on it. He said the reaction from users has been "fairly muted."
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