The seemingly innocuous targeted ads appearing across websites and apps have a dark underbelly - they're feeding a massive surveillance ecosystem that puts billions of people's private data at risk. Through a process called real-time bidding (RTB), personal information is being broadcast to thousands of companies each time an ad loads on screen.
RTB works by conducting lightning-fast auctions whenever someone visits a website with ad space. The site sends details about the visitor - including location, device information, interests and demographics - to an auction company, which then broadcasts this data to potential advertisers who bid for the ad spot. While only one advertiser wins, all participants receive and can store the user's personal data.
This system creates a backdoor for extensive data collection. Anyone posing as an ad buyer can tap into this stream of sensitive information about billions of individuals. Data brokers exploit this vulnerability to harvest and sell personal details to virtually anyone willing to pay - from marketers to government surveillance agencies.
The Federal Trade Commission recently took its first enforcement action against the misuse of RTB data, targeting data broker Mobilewalla. The company collected information on over a billion people from ad auctions without placing any ads, then sold it for tracking union organizers, protesters, and healthcare workers. They even categorized people into sensitive groups based on pregnancy status, religion, and sexual orientation.
Government agencies regularly capitalize on RTB data for surveillance. Defense and intelligence organizations have purchased location data on billions of devices gathered through ad auctions. Surveillance companies have also created tracking tools by posing as advertisers to acquire RTB data, marketing their capabilities to security agencies worldwide.
The privacy risks extend to national security concerns. Researchers warn that RTB could allow foreign actors to obtain compromising details about American defense personnel and political figures. In one instance, Google's ad auctions transmitted sensitive data to a Russian ad company months after U.S. sanctions.
While individuals can take some protective steps like disabling mobile ad IDs and using tracker-blocking tools, the real solution requires systemic change. Privacy advocates argue for banning online behavioral advertising entirely. This would eliminate companies' incentive to collect and share personal data through RTB, while still allowing contextual ads based on webpage content rather than user profiles.
As it stands, the simple act of seeing an online ad means potentially exposing intimate details about yourself to thousands of unknown entities. The surveillance implications of this advertising system demand urgent attention and reform.