by Wes Davis at The Verge
Researchers found that, on average, Facebook received data from 2,230 different companies for each of the 709 volunteers. One extreme example showed that “nearly 48,000 different companies were found in the data of a single volunteer.” In total, Facebook data archives showed that 186,892 companies had provided data on all of the study’s participants.
Volunteers recruited with help from The Markup pulled their personal data from Facebook using its Download Your Information tool and shared it with the researchers.
Companies using Meta’s advertising platform upload customers’ personal information and buying habits, which Meta uses to serve targeted ads to those people or people with similar profiles. The researchers believed that the ease of “microtargeting” campaigns to specific user data accounted for the fact that 96,000 of the companies listed were only targeting one of the volunteers…