Social networking site Facebook has said that it will no longer automatically tell people's friends of their online activities after an outcry claiming that its new advertising service was a violation of users' privacy.
The site said that it has changed the default settings so that users must specifically request that their details can be published by the Beacon system, which was made live on the site last week.
The Beacon system took information about Facebook users' activity at partner businesses such as online retailers and published the details on Facebook for a person's Facebook friends to see.
Users complained that they had not chosen to publish their shopping activity, and one man said that he found out what his girlfriend had bought him for Christmas because of the unwanted service.
Facebook has now said that it will seek explicit permission before publishing details of activity on third party sites, and that if no response is given it will keep the details private. Facebook will continue to request permission to publish stories, however.
"Users must click on 'OK' in a new initial notification on their Facebook home page before the first Beacon story is published to their friends from each participating site," said a Facebook statement announcing the changes. "We recognize that users need to clearly understand Beacon before they first have a story published, and we will continue to refine this approach to give users choice."
"If a user does nothing with the initial notification on Facebook, it will hide after some duration without a story being published. When a user takes a future action on a Beacon site, it will reappear and display all the potential stories along with the opportunity to click 'OK' to publish or click “remove” to not publish," it said.
Facebook users were shocked to find their online shopping habits published to friends, and some reportedly began deleting their Facebook profiles, prompting the company to take action.
A petition by civic action group MoveOn.org received 50,000 signatures in support of its stance against Beacon in 10 days, and a group was set up within Facebook called 'Facebook, stop invading my privacy'.
Users of online social networking sites are increasingly being warned about the dangers of publishing large amounts of personal information on the site. It has been used by employers to vet potential workers and security experts have warned that profiles could yield valuable information to identity thieves.
Facebook has been under pressure before in relation to its privacy policies. A petition gathered 700,000 signatures in 2006 over requested improvements to the site's privacy.
The UK's Information Commissioner recently said that his office would investigate the company over its refusal to delete a user's profile. It received a complaint from a user who said that he could de-activate his profile and that it still remained on Facebook's servers, albeit not accessible to the public.