Facebook assumed it had the consent of users to share information about them that it collected through the Beacon advertising service if they did not use the opt-out feature.
Facebook changed Beacon to be an “op-tin” service and gave users the ability to disable it completely. The company utterly failed to grasp the extent to which the service violated its users’privacy as well as the uproar such a service was likely to cause. The same thing occurred when Facebook introduced its News Feed feature