The US government buys your user data. Here’s what it does with it

In the ODNI's report, commercially available information (CAI) is defined as “information that is available commercially to the general public, and as such, is a subset of publicly available information.” This information can include your location, credit history, insurance claims, criminal records, employment history, income ethnicity, purchase history, and personal interests.

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Although apps and websites will disclose that some of this information is not linked to your identity, the report says it's possible to “deanonymize [anonymous data] and identify individuals, including US persons,” via reverse engineering.

Because CAI is available commercially, the information can be acquired from a third-party data broker, typically in exchange for money. The report defines these data brokers as entities maintaining sophisticated databases full of US citizens' user data.

But data brokers also obtain publicly available information, such as voting registration, bankruptcy information, and web-browsing activity, from cookies. Usually, citizens are unaware that this information is public and that data brokers obtain it.

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Data brokers rely on website registration and cookies to track consumers' online activity and sell the data to advertisers to target consumers with ads. This business practice makes user data a highly valuable commodity.