Chris McQueen completed leukemia treatment 18 months ago, but his phone continued displaying ads for fake cancer cures. Juice cleanses, unproven Mexican clinics, and “natural” remedies kept appearing during doctor visits and bloodwork appointments. The ads persisted because his location data—collected by data brokers—revealed his movements.
McQueen’s experience is shared by many patients across the U.S. who report seeing targeted ads for untested treatments after visiting hospitals, abortion clinics, or support groups. A 2022 American Medical Association survey showed that 92% of patients believe their health data should not be sold. However, most do not realize their smartphones leak location signals even in HIPAA-protected spaces.
The issue has persisted for years. In August 2024, the Federal Trade Commission imposed a fine on Kochava, a data broker, for selling location data tied to hospitals, churches, and abortion clinics. The settlement required Kochava to stop sharing such data without consent, but enforcement has been inconsistent. California’s 2020 privacy law granted consumers the right to delete their data, yet a Stanford study found only 9% of brokers comply with these requirements.
State Laws Clash Over Privacy Protections
California’s progress faced a setback in September 2024 when Governor Gavin Newsom vetoed a bill aimed at banning the sale of sensitive location data. He argued the measure went too far. Meanwhile, six states, Connecticut, Delaware, Maryland, New Jersey, Oregon, and Virginia, have restricted precise geolocation sales, though digital advertisers continue lobbying against stricter rules.
Data brokers claim location data itself is not sensitive, only its broad collection is. F. Mario Trujillo, a senior attorney at the Electronic Frontier Foundation, disagrees. Advertisers argue targeted ads save consumers time and money, but critics highlight the high profit margins of tech giants such as Alphabet, Meta, and Microsoft. A 2024 Federal Reserve report found these companies’ margins are at least twice the industry average.
The risks extend beyond ads, including data breaches. A 2023 Consumer Reports investigation uncovered errors in broker profiles, such as one person’s file listing them as both male and female, with four ages and three fake jobs. The Privacy Rights Clearinghouse identified 750 active data brokers in the U.S., many unregistered and difficult to opt out of.
How Data Brokers Exploit Patient Tracking
Patients face a dilemma: share data to access services or risk exclusion. Even when brokers remove sensitive locations from profiles, they can still track routes to infer destinations, such as mapping a patient’s path to a medical facility. The Electronic Frontier Foundation refers to this as “blackout windows” on a map.
Doctors are also affected. Julien Cavanagh, an Atlanta neurologist, now asks patients about online supplements when they arrive with unexplained symptoms.
Without uniform regulations, consumers lack ways to verify profile accuracy or opt out entirely. While some states, like California, offer centralized portals for data deletion requests, compliance remains low.
Advertisers defend targeted ads as efficient and cost-effective, claiming they improve consumer choice. Trade groups like 4As Health, a subsidiary of the American Association of Advertising Agencies, argue that digital advertising supports free services and economic growth.
