Privacy advocates Tuesday called for government regulators to investigate Facebook's tracking of users even when they're on third-party sites, saying the change might violate a previous privacy agreement Facebook made with the government.
Last month, the social networking site announced that, like many other sites, it would track not just what users do on Facebook but also on many other sites to better tailor advertising to users' interests.
Members of two advocacy organizations, the European Consumer Organization and the U.S.-based Center for Digital Democracy, called for the Federal Trade Commission to halt the practice.
They also want the FTC to investigate whether the shift by Facebook violates an agreement the company made with FTC to better inform users about changes to their privacy and how their content would be used.
Facebook had been accused of telling its users they could keep their information private while repeatedly allowing that information to be shared and made public. Facebook and the FTC came to an agreement in 2012 that the company would improve how it notified users about changes to data privacy; Facebook also agreed to gain users' consent before sharing their information.
Though Facebook got heat from privacy advocates last month for tracking its users offsite, the announcement was paired with other changes that were welcomed by its critics. Users, the company announced, would have more control about what advertisers knew about them.
"If you don't want us to use the websites and apps you use to show you more relevant ads, we won't. You can opt out," the company said at the time.
In a letter to government regulators, the privacy advocates expressed "deep alarm" about the new tracking.
"Facebook's data collection practices involve a closely woven relationship among Facebook, its advertising partners, data-broker companies, and various marketing applications services," the letter read. " The extent of this complex network of data collection practices is not immediately obvious to consumers; in fact, users must click through several different parts of the Facebook website to discover the existence of many of Facebook's data partners."
Facebook defended its changes in a statement: "The level of control people have over advertising on Facebook exceeds industry standards. Anyone can opt out of advertising based on the websites they visit and apps they use, and we offer ad preferences, a way for people to add and remove interest categories to improve the ads they see on Facebook."
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