BILLIONAIRE Mark Zuckerberg has halted the sale of his Facebook stock after the company's value collapsed last year.

The controversial 34-year-old has seen his company fall from grace, and failed to sell a single share in the last three months of 2018.

5 Facebook boss Mark Zuckerberg is one of Silicon Valley's most hated figures Credit: AFP or licensors

Back in September 2017, Zuck promised to flog between 35million and 75million of his Facebook shares over 18 months.

It was part of a promise to give away most of his fortune, which requires converting stocks to hard cash.

Since then, he's sold about 30.4million shares worth roughly $5.6billion (£4.4billion).

But Bloomberg says that the Facebook CEO has stopped selling shares after 2018 saw Facebook's worth plummet.

5 2018 saw the ashen-faced CEO appear before US Congress for questioning over Facebook's dodgy privacy antics Credit: The Mega Agency

In just a few days in December, Facebook's stock price slumped by nearly $10billion (£7.4billion) after sealed court documents about the firm were released to the public.

The secret files – which contain emails from billionaire boss Mark Zuckerberg – revealed the inner workings of Facebook, and the company's blatant disregard for user privacy.

And between July and December, Facebook lost around £172billion, as the year saw Zuck's social network become the world's most notorious tech firm.

At the time, it was equivalent to losing the combined value of Netflix (£94.2billion), Twitter (£20.5billion), Snapchat (£5.78billion) and Sony (£49.6billion).

Facebook has also lost £92billion in value since the beginning of 2018.

5 Leaked emails revealed the ruthless response Mark Zuckerberg (MZ) gave when asked if Facebook should restrict Vine's access to user data to damage the rival app – the publication of which caused Facebook's value to plummet late last year

5 The company's stock price plummeted between July and December 2018 Credit: YCharts / The Sun

The Harvard dropout came under fire after a New York Times exposé revealed that Facebook secretly let Netflix and Spotify read your private messages.

The private partnerships were exposed through leaked Facebook files that highlight the company's ongoing failure to protect user's privacy.

This leak also revealed that Facebook had given user data to Yandex – Russia's equivalent to Google – despite the company's alleged "direct line" to Kremlin spies.

Facebook CEO Mark Zuckerberg says social media regulation is inevitable as US Congress grill him over data misuse

A separate report from Gizmodo found that Facebook was still tracking your exact location, even if users told it not to.

The sinister tactic sees Facebook skirt your settings to serve you location-based advertising, helping Zuckerberg make even more money.

And late last year, Facebook admitted a major cybersecurity blunder: it had given app makers access to private photos from your smartphone's camera roll.

These were photos that had never been posted to Facebook, but were sent to app makers without user permission.

Facebook believes that around 6.8million users were exposed by the gaffe.

5 34-year-old Zuckerberg has a net worth of around £42.7billion, so it's unlikely he loses much sleep over your privacy being exposed Credit: EPA

Facebook's streak of bad luck largely began in March, when the company was forced to admit it had given away user info without their consent.

It led to Mark Zuckerberg being confronted by useless lawmakers at the US Congress, followed by an equally confused hearing at the EU.

Matters were made worse when Facebook admitted in September that it had given hackers complete access to 30million user accounts – due to three different coding cock-ups on its website.

Some spectators have suggested Mark Zuckerberg has "lost control" of Facebook, including Belgian and EU politician Guy Verhofstadt.

How to delete Facebook – easy steps to QUITTING for good Here's how to quit right now... Temporarily deactivating your account is really easy – and you can log back in at any time to undo it: Follow this link

Choose "Manage your account" and then scroll down to click "Deactivate your account" Facebook has a special page for permanent account deletion, which you can find below: Click here for deletion page It's worth noting that you can also download a copy of your information from Facebook as a back-up: Click the down arrow at the top right of any Facebook page and select Settings

Click "Download a copy of your Facebook data" at the bottom of the General Account Settings

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The situation is now so bad at Facebook that workers are turning on their dodgy boss.

Reports suggest Facebook staff have resorted to buying burner phones to allow them to badmouth their superiors without fear of being recorded.

Former employees described a "toxic and hostile" work environment at the social media giant, which has been hit by a wave of data leaks and fake news scandals over a torrid few years.

One former senior staff member told Buzzfeed News that workers were eyeing up a change of leadership.

"People are hoping for a Sundar or Dara moment," the worker said, referring to Google chief Sundar Pichai and Uber's new boss Dara Khosrowshahi.

Another said paranoia among employees meant they were using secondary phones to gossip about colleagues.

The source revealed: "People now have burner phones to talk s**t about the company - not even to reporters, just to other employees."

They added that seething bosses are "spouting full-blown anti-media rhetoric, saying that the press is ganging up on Facebook".

"It's the bunker mentality. These people have been under siege for 600 days now. They're getting tired, getting cranky - the only survival strategy is to quit or fully buy in."

Facebook's Mark Zuckerberg apologises to EU lawmakers over data leak at the European Parliament

Facebook has suffered major losses in terms of execs, too.

WhatsApp co-founder Jan Koum left the company in April this year, and was followed by Instagram founders Kevin System and Mike Kreiger in September.

Mark Zuckerberg is now under pressure from some investors to stand down from the company's chief exec position.

Facebook declined to comment on this story.

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