A study [PDF] by Consumer Reports and non-profit The Markup concluded that for the average lone Facebook user, 2,230 companies, and in some cases more than 7,000, will hand over that person’s information to Facebook. We’re told 709 volunteers took part in the study over three years, during which time 186,892 organizations passed data about them to the Meta-run empire.
The article (including a linkto the PDF by Consumer Reports: Thousands of businesses hand over your info to Facebook • The Register
(Apparently unironically, The Register site is infested with Google/Doubleclick, so ensure you have appropriate tracker-blocking enabled.)
Here’s a direct link to the Consumer Reports article: New Report: CR’s Who Shares Your Information with Facebook Study - Innovation at Consumer Reports