Don't be surprised that the FBI is buying your location data

"The FBI has confirmed to the Senate it is once again buying data which can be used to track the locations of US citizens. That may have surprised the people who thought the precedent in Carpenter v. United States prohibited it. But while that case examined if it was legal for law enforcement to obtain location data from mobile networks without a warrant, here the FBI and other agencies have found a way to skirt the Fourth Amendment entirely."

"When your phone is connected to the internet, it broadcasts about itself, and so do the apps and platforms you use. That information includes your IP address and device type, as well as your longitude and latitude if your device has GPS. This data, known as Bidstream, alongside any third party cookies tied to your device, enables the process of Real Time Bidding (RTB)."

"Data brokers can easily combine the two streams of information to build out a fairly extensive picture of you as a person, and what advertisers will be the most interested in targeting you with, by pairing location and IP address broadcast over ad networks with deterministic data from platform signups and financial institutions."

Law enforcement agencies, including the FBI, have found a legal workaround to obtain location data on US citizens by purchasing it from advertising technology companies rather than directly from mobile networks. This approach bypasses Fourth Amendment protections established in Carpenter v. United States. The data originates from smartphones broadcasting information including IP addresses, device types, GPS coordinates, and third-party cookies through the advertising ecosystem. Real Time Bidding (RTB) auctions user attention to advertisers in milliseconds, requiring extensive personal data. Data brokers aggregate this information with deterministic data from user signups and financial institutions, creating comprehensive profiles that enable targeted advertising and law enforcement tracking.

Read at Engadget