Update 10/05/2021 2:15pm:

The outages on Facebook, Instagram, and WhatsApp yesterday reportedly caused Facebook head Mark Zuckerberg to lose over $6 billion within a few hours. The outages reportedly came after a former employee Frances Haugen called out the company as a whistleblower. Now, Zuckerberg and Facebook

Zuckerberg addressed users of the platforms via Twitter and said, “Facebook, Instagram, WhatsApp, and Messenger are coming back online now. Sorry for the disruption today—I know how much you rely on our services to stay connected with the people you care about.”

The VP of Engineering and infrastructure for Facebook—Santosh Janardhan, spoke on the outage and said, “Our engineering teams have learned that configuration changes on the backbone routers that coordinate network traffic between our data centers caused issues that interrupted this communication. This disruption to network traffic had a cascading effect on the way our data centers communicate, bringing our services to a halt.” The VP noted there was “no evidence” that data was compromised during the massive outage.

source: COMPLEX

Original 10/04/2021 5:02pm:

Facebook CEO Mark Zuckerberg has fallen down the list of the world's billionaires after losing billions amid outages on the social media website. This comes after former Facebook employee Frances Haugen coming forward as the whistleblower who filed complaints with federal law enforcement. 

According to Bloomberg, Facebook stock dropped 5% on Monday (October 4), which took Zuckerberg's net worth down to $120.9 billion. He now sits below Bill Gates at No. 5 on the Bloomberg Billionaires Index. Bloomberg also pointed out that Zuckerberg has lost around $19 billion since September, which is when the Wall Street Journal published a series of private Facebook research documents that are damning to the company. 

As of time of publishing this article, Facebook and Instagram are still down, with Facebook telling users via Twitter they are "working to get things back to normal as quickly as possible."

Source: Bloomberg