The Shadow Market of Personal Data
Data brokers are companies that collect information about consumers from public records, purchase history, and web tracking, aggregate it into comprehensive profiles, and sell it to other organizations.
According to a 2023 FTC report, some data brokers possess thousands of data points on individuals, including sensitive information like geolocation data linked to reproductive health clinics.
The Supply Chain of Data
- Collection: SDKs in mobile apps, third-party cookies on websites, and public records (voter registration, property records).
- Aggregation: Using identifiers like email addresses (often hashed) or phone numbers to link disparate datasets.
- Sale: Selling "audiences" to advertisers, or raw data to hedge funds, insurance companies, and even law enforcement agencies.
Example: Location Data
A weather app asks for location permission. It includes a third-party SDK from a monetization partner. That partner sells a live feed of coordinates to a data broker. The broker sells access to an intelligence firm, which sells it to the government, bypassing the need for a warrant.
Frequently Asked Questions
Can I opt out?
In jurisdictions like California (CCPA) and Europe (GDPR), yes. However, the process is often deliberately obtuse, and there are thousands of brokers.
Is this legal?
In the US, largely yes, due to the lack of a comprehensive federal privacy law. Data is considered the property of the company that collected it.