Wired: “These firms could track whether you’ve visited your therapist’s office or your ex’s house. And without regulation, they’re a threat to democracy…In a new report for the Cyber Policy Program at Duke University’s Sanford School of Public Policy, I surveyed 10 major data brokers and the sensitive data they advertise. They openly and explicitly promulgate data on individuals’ demographic characteristics (from race to gender to income level) and political preferences and beliefs (including support for the NAACP, ACLU, Planned Parenthood, and the National LGBTQ Task Force), and on current US government and military personnel. Several of these firms also market another disturbing product: Americans’ geo-locations.

Acxiom, one of the largest brokers with data on billions of people worldwide, advertises “location-based device data” on individuals. Need to know if someone has visited a location multiple times in the past 30 days, like a church, their therapist’s office, or their ex’s house? They’ve got you covered, according to a company marketing document. What about other insights based on individuals’ locations? Check out data from marketing firm NinthDecimal, according to a 2018 fact sheet, an Acxiom “partner” that provides “mobile device location and location context insights.” Military personnel, Acxiom says, can be located too: It offers “verification and location of military servicemen (deployed but missing from base)” as part of commercial work for credit card issuers and retail banks…”