Julia Angwin, Terry Parris, Jr., and Surya Mattu reported that, since 2012, Facebook has been buying sensitive data about users’ offline lives from data brokers and combining this information with the online data it collects in order to sell this information to advertisers who seek to target specific types of Facebook users for their products and services. Facebook, they reported in September 2016, uses a “particularly comprehensive set of dossiers” on its more than two billion members in order to “offer marketers a chance to target ads to increasingly specific groups of people.” As Angwin, Parris, and Mattu described in that report, “we found Facebook offers advertisers more than 1,300 categories for ad targeting—everything from people whose property size is less than .26 acres to households with exactly seven credit cards.”
Their December 2016 report quoted Jeffrey Chester, executive director of the Center for Digital Democracy. Facebook, Chester said, is “not being honest . . . Facebook is bundling a dozen different data companies to target an individual customer, and an individual should have access to that bundle as well.”
Facebook collects information on users in many ways beyond users’ posts and “likes.” For instance, many websites include a Facebook link where a visitor to the site can like it on Facebook. In such cases, even if the website visitor does not choose to like the site on Facebook, Facebook is still able to track that the page was visited—linking back to the user. The data brokers from which Facebook buys additional information track offline sources, such as supermarket loyalty cards, mailing lists, and public records information (which includes records of home or car ownership).
Facebook seeks to puts users at ease by providing an opt-out option. However, as Angwin, Parris, and Mattu wrote, “Limiting commercial data brokers’ distribution of your personal information is no simple matter.” Even getting data brokers to share the information that they have about you (and can sell) could require sending the last four digits of your social security number, as in the case of Acxiom, one of six data brokers from which Facebook buys personal information. Reporter Julia Angwin noted that in 2013 she tried to opt out from as many data brokers as she could find. Sixty-five of the ninety-two brokers she found required her to submit some form of identification. “In the end, she could not remove her data from the majority of providers,” despite the fact that she had not signed up for any of these tracking services herself, the December ProPublica story reported.
One of the ways ProPublica gathered data for its report on Facebook’s data collection processes was by asking Facebook users to share with ProPublica the categories of interest that the site assigned to them. ProPublica collected more than 52,000 unique attributes that Facebook had used to classify users’ interests.
Although Facebook’s methods of collecting data about the platform’s users have received corporate coverage, this reporting has not explained the specific tactics used or the information obtained by data brokers. For instance, a 2010 Wall Street Journal article described how Facebook reported that “it had placed some developers on a six-month suspension from its site” because “a data broker” had “been paying application developers for identifying user information.” Rather than appearing as an isolated and unusual case as the Wall Street Journal report implied, Facebook’s practice of engaging data brokers and selling user data to advertisers seems, according to ProPublica’s 2016 reports, to be systemic and, apparently, entirely acceptable to Facebook.
Julia Angwin, Terry Parris, Jr., and Surya Mattu, “Breaking the Black Box: What Facebook Knows About You,” ProPublica, September 28, 2016, https://www.propublica.org/article/breaking-the-black-box-what-facebook-knows-about-you.
Julia Angwin, Terry Parris, Jr., and Surya Mattu, “Facebook Doesn’t Tell Users Everything It Really Knows About Them,” ProPublica, December 27, 2016, https://www.propublica.org/article/facebook-doesnt-tell-users-everything-it-really-knows-about-them.
Student Researcher: Jonnie Zambrano (Citrus College)
Faculty Evaluator: Andy Lee Roth (Citrus College)