Earlier today, the Wall Street Journal published evidence that Google has been circumventing the privacy settings of Safari and iPhone users, tracking them on non-Google sites despite Apple's default settings, which were intended to prevent such tracking. [...]
Unfortunately, that had the side effect of completely undoing all of Safari's protections against doubleclick.net. It caused Safari to allow other DoubleClick cookies, and especially the main "id" tracking cookie that Safari normally blocked. Like a balloon popped with a pinprick, all of Safari's protections against DoubleClick were gone.
Google Circumvents Safari Privacy Protections - This is Why We Need Do Not Track
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