A Consumer Reports study found that thousands of companies contribute to Facebook’s data stores on each person.
Facebook gets data on individual users from many thousands of companies, and a new study (PDF) from Consumer Reports tried to put more exact numbers on it.
Researchers found that, on average, It 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.
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