Why personalized ads advance surveillance technologies

Real-time bidding (RTB) technology, a cornerstone of online advertising, has evolved into a major privacy concern by exposing the personal data of billions of individuals to advertisers, data brokers, and even governments. This pervasive and largely unregulated technology powers the targeted ads seen on nearly every website and app, but its dark implications extend far beyond advertising. RTB has become a mechanism for mass surveillance, national security risks, and the commodification of personal data, all while undermining individual privacy.

RTB is the process by which targeted ads are selected in milliseconds-long auctions. An article by the Electronic Frontier Foundation non-profit organization has shed light on this silent yet dangerous abuse of the technology, explaining, that when a user visits a website or app, the platform sends a request to an ad auction company, sharing information about the user’s location, interests, demographics, and device details. This information, known as bidstream data, is broadcast to thousands of advertisers. Each advertiser evaluates the data and decides whether to bid for the ad space. While only one advertiser wins, all participants in the auction gain access to the data, creating significant privacy vulnerabilities.

The RTB system incentivizes the collection of personal data. Websites and apps that harvest and share more detailed user information attract higher bids, while advertisers and data brokers continuously track users to improve their bidding strategies. This results in an ecosystem where personal data is freely traded at an immense scale. Every day, hundreds of billions of RTB requests are broadcast globally, with thousands of real or fake ad buyers collecting data on billions of users.

The Dangers of Real-Time Bidding

RTB’s design enables the exploitation of personal data by advertisers, data brokers, and even governments. The US Federal Trade Commission (FTC) recent enforcement action against data broker Mobilewalla exemplifies these dangers. Mobilewalla collected bidstream data on over a billion people without placing ads and sold the data for invasive purposes, such as tracking union organizers, identifying attendees at Black Lives Matter protests, and categorizing individuals based on characteristics like pregnancy, religion, or sexual orientation. The FTC found this practice violated the FTC Act and imposed restrictions on Mobilewalla’s data collection.

According to the article, government surveillance is also exploiting this RTB data, as data brokers have sold sensitive bidstream data to intelligence agencies as cases involving the American FBI and ICE have shown. Several companies like Rayzone and Patternz have developed surveillance tools using RTB data, which allow governments to track individuals’ movements, link their locations to personal identities, and access their browsing histories. The indiscriminate nature of RTB creates a national security risk, as foreign actors could acquire sensitive data about defense personnel or political leaders. For example, Google’s ad auctions inadvertently sent sensitive data to a Russian company even after US sanctions were imposed.

The problems with RTB are systemic. The process inherently prioritizes data sharing, broadcasting sensitive user information to thousands of entities with little to no oversight. This indiscriminate data sharing not only enables exploitative advertising but also facilitates harmful practices like predatory targeting, where vulnerable individuals are served ads for payday loans or other exploitative products.

Addressing the Risks

Protecting individual privacy in an RTB-dominated ecosystem is challenging. The article suggest steps such as disabling mobile advertising IDs, auditing app permissions, and using browser extensions like Privacy Badger to block trackers. However, these measures offer limited protection and place the burden of privacy defense on individuals.

A more effective solution is banning online behavioral advertising altogether. Behavioral advertising, which targets users based on their online activity, drives the RTB system and incentivizes the collection and sharing of personal data. Shifting to contextual advertising—where ads are targeted based on the content of a webpage rather than user behavior—would significantly reduce privacy risks. Contextual ads would still allow advertisers to reach relevant audiences without broadcasting sensitive user data to countless companies.

As RTB continues to dominate online advertising, it is critical to reexamine the trade-offs between targeted ads and privacy. The current system extracts immense value from personal data at the expense of individual rights, but this need not remain the status quo. By prioritizing privacy over surveillance, the authors believe that a safer, more ethical digital landscape can be created where advertising serves its purpose without exploiting users.

By Nazrin Sadigova