How to Check If Cambridge Analytica Could Access Your Facebook Data

In 2014, a researcher named Alexander Kogan created a personality quiz that 270,000 Facebook users would go onto install. From those downloads alone, he was able to harvest the personal information of up to 87 million people, according to Facebook's most recent estimate. He then passed that data along to Trump-affiliated political firm Cambridge Analytica, which would use it to target voters in the 2016 presidential election. Now Facebook has finally released a tool that lets you know if you were affected. Beginning at noon ET on Monday, some Facebook users will see one of two messages at the top of their News Feed.