The Facebook share price has dropped from US$185.09 to today's US$168.15, which represents a fall of 9% since the weekend.
This has all blown up after British business Cambridge Analytica, a data analytics company, allegedly gathered people's personal data without their consent.
Previously, Cambridge Analytica had been credited with helping the Trump campaign win the election and also helping the Brexit side win.
UK TV station Channel 4's News team sent a reporter undercover to meet some of the top people of Cambridge Analytica including the boss Alexander Nix. The undercover reporter pretended to be a Sri Lankan trying to influence an election.
Mr Nix was supposedly filmed saying that he could spread disinformation about rival political candidates such as setting up meetings with Ukrainian prostitutes or faking bribery.
It must be said that Cambridge Analytica denies the claims.
Facebook is being slammed because of how this unfolded. Back in 2014, a quiz was carried out for users to work out their personality type. This quiz was created by Aleksandr Kogan.
The quiz was designed to take people's personal Facebook data as well as their friend's data. You can no longer do this, according to Facebook.
Christopher Wylie, who previously worked at Cambridge Analytica, alleges that when 270,000 people took the quiz, the personal data of around 50 million users was taken without their consent. This data was allegedly then sold to Cambridge Analytica which it then used to carry out targeted ads to show pro-Trump messages.
Foolish takeaway
This is not a good look for Facebook and there could be more unknown stories like this out there. I'm sure Facebook will get through this, it has a variety of other social media businesses like Instagram to grow with that have nothing to do with the scandal. However, it's bad for Mr Zuckerberg's net worth and this raises questions about privacy and propaganda in this social media era that we live in.
