PART 2 - FOUR HIDDEN CHIMNEYS CHAPTER 9: ARE UNICORNS REALLY WHITE? From Connecting to Selling Us

"Facebook Exchange was introduced in 2012 as a real-time bidding advertising system using third-party browsing cookies for retargeting."

Contemporary reporting describes Facebook Exchange as a real-time bidding system in which browsing cookies could trigger advertiser bids when a user returned to Facebook.

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