Here’s what’s been happening on Wall Street overnight

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Facebook’s share price dropped close to 8% Monday, most likely thanks to the news that the political-research firm Cambridge Analytica used its site to harvest 50 million user profiles illegitimately.

The Guardian and The New York Times reported on Saturday that Cambridge Analytica had accessed data from 50 million Facebook users during the 2016 US presidential campaign without their permission. It used that information for highly targeted political ads on Facebook. Here’s the latest:

Elsewhere in tech news, Wall Street’s coming around to a worrying consensus about Apple. Here’s our latest:

And in markets news:

Lastly, the 24-year-old billionaire heiress to the Dell fortune left social media after exposing her family to security risks.