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This work seeks to understand what “they” (Web advertisers) actually do with the information available to them. We analyze the ads shown to users during controlled browsing as well as examine the inferred demographics and interests shown in Ad Preference Managers provided by advertisers. In an initial study of ad networks and a focused study of the Google ad network, we found many expected contextual, behavioral and location-based ads along with combinations of these types of ads. We also observed profile-based ads. Most behavioral ads were shown as categories in the Ad Preference Manager (APM) of the ad network, but we found unexpected cases where the interests were not visible in the APM. We also found unexpected behavior for the Google ad network in that non-contextual ads were shown related to induced sensitive topics regarding sexual orientation, health and financial matters. In a smaller study of Facebook, we did not find clear evidence that a user’s browsing behavior on non-Facebook sites influences the ads shown to the user on Facebook, but we did observe such influence when the Facebook Like button is used to express interest in content. We did observe Facebook ads appearing to target users for sensitive interests with some ads even asserting such sensitive information, which appears to be a violation of Facebook’s stated policy.