Ad Observer (Facebook)

Facebook is an American online social media and social networking service owned by Facebook, Inc. 

Recently the Surgeon General of the United States weighed in on the spread of disinformation on major platforms and its effects on people and society. He echoed the calls of researchers, activists and organizations, like Mozilla, for the major platforms to release more data, and to provide access to researchers in order to analyze the spread and impact of misinformation.  Yet Facebook has again taken steps to shut down this exact kind of research on its platform, a troubling pattern we have witnessed from Facebook including sidelining their own Crowdtangle and killing a suite of tools from Propublica and Mozilla in 2019.  

Most recently, Facebook has terminated the accounts of New York University researchers that built Ad Observer, an extension dedicated to bringing greater transparency to political advertising that was critical for researchers and journalists during the presidential election. Facebook claims the accounts were shut down due to privacy problems with the Ad Observer.  In our view, those claims simply do not hold water. We know this, because before encouraging users to contribute data to the Ad Observer, which we’ve done repeatedly, we reviewed the code ourselves. And in this blog post, we want to explain why we believe people can contribute to this important research without sacrificing their privacy.  

Anytime you give your data to another party, whether Facebook or Mozilla or researchers at New York University, it is important that you know whether that party is trustworthy, what data will be collected, and what will be done with that data. Those are critical things to consider before you potentially grant access to your data. And those are also key factors for Mozilla when we consider recommending an extension.

Before Mozilla decided to recommend Ad Observer, we reviewed it twice, conducting both a code review and examining the consent flow to ensure users will understand exactly what they are installing. In both cases the team responsible for this add-on responded quickly to our feedback, made changes to their code, and demonstrated a commitment to the privacy of their users. We also conducted an in-depth design review of Ad Observer, the results of which can be found here

We decided to recommend Ad Observer because our reviews assured us that it respects user privacy and supports transparency. It collects ads, targeting parameters and metadata associated with the ads. It does not collect personal posts or information about your friends. And it does not compile a user profile on its servers. The extension also allows you to see what data has been collected by visiting the “My Archive” tab. It gives you the choice to opt in to sharing additional demographic information to aid research into how specific groups are being targeted, but even that is off by default.

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