Whistleblower's story explains why Facebook booted a Trump-linked data firm

Now we know why Facebook gave Cambridge Analytica the boot on Friday. What's less clear is why it took so long.
The social media company was aware as far back as late 2015 that, starting in early 2014, the Trump-linked U.K data firm had secretly harvested profile data belonging to 50 million users, according to a follow-up report from The Observer. The paper calls it Facebook's biggest data breach to date.
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The details come f