SAN FRANCISCO - Saying it went too far in its pursuit of profit, the popular Internet hangout Facebook Inc. is allowing its 55 million users to permanently turn off its "Beacon'' advertising program.

The program tracks their activities at other websites.

The privacy control, announced in a Wednesday apology by Facebook founder Mark Zuckerberg, will likely decrease participation in a month-old program that the Palo Alto-based startup had hailed as an advertising breakthrough.

Facebook users protested Beacon as a flagrant violation of privacy.

The program enables Facebook to track their purchases and other actions at dozens of websites and then broadcast the data within its social network as items on other users' "news feeds.''

"We've made a lot of mistakes building this feature, but we've made even more with how we've handled them,'' Zuckerberg wrote on Facebook's blog.

"We simply did a bad job with this release, and I apologize for it.''

Adam Green, a spokesman for MoveOn.org, said empowering users to block Beacon entirely "is big step in the right direction, and we hope it begins an industrywide trend.''

He said he hopes it "puts the basic rights of Internet users ahead of the wish lists of corporate advertisers.''

MoveOn is an advocacy group which organized a petition against Beacon that more than 65,000 Facebook users signed.

Critics worry that Facebook and other popular websites will deploy increasingly sophisticated technology to shadow Web surfer's activities in an attempt to tailor advertising more and more specifically.

  • If you are a Facebook user, you can change your privacy settings