On a Friday afternoon in July 2015, Mark Zuckerberg stood in front of a couple hundred employees at Facebook's Menlo Park, Calif., headquarters, a video camera there to record his words for thousands of other employees around the globe.
Zuckerberg, usually calm and a natural introvert, was uncharacteristically angry.
News of Facebook's previously secret messaging assistant, M, had leaked earlier that week to the press. The Facebook CEO made a promise to his employees: We're going to find the leaker, and we're going to fire them.
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At another company meeting a week later, Zuckerberg delivered an update: The culprit, he said, had been caught and fired. Many of those in attendance applauded.
Both the leak and the ensuing witch hunt are Facebook rarities. Unlike tech companies such as Apple and Snapchat, which keep employees in the dark about projects and ambitions, Facebook routinely shares all kinds of secrets with all of its workers at Friday afternoon Q&A sessions that Zuckerberg has been running for a decade.
What's most surprising: Almost none of it leaks out.
Sources say Zuckerberg uses these weekly meetings to tell his nearly 16,000 employees details of yet-to-be-released products, like news reader app Paper or Snapchat competitor Slingshot — and M, the AI assistant.
He'll open up about the company's product strategy, like its push into live video. And Zuckerberg will also share his personal opinions on competitors like Snapchat and Twitter, and even Facebook's board members.

Almost nothing is off limits. And almost nothing leaks to the press, even though Facebook's entire workforce — including its interns — have access to the meetings.
"That level of transparency is alarming when you see it at first," said one former employee. "But there's something [special] about knowing you're getting an unfettered response."
And that special feeling — that employees have access to information and an open, unscripted, says-whatever-he-thinks Zuckerberg — helps keep what happens at the weekly meetings inside the weekly meetings. Usually.
"If we're going to have this open culture, there's a little bit of a pact [around not leaking secrets]," explained another former employee.
There are formal pacts as well. Facebook puts new employees through media training and warns them that they could be fired for leaking company info. And Zuckerberg routinely reminds Facebook employees that his weekly Q&As are meant to be private.
But at Facebook there's another deterrent: Shame.
We spoke with more than a half-dozen current and former employees, and almost all of them mentioned peer pressure as a key motivator for keeping secrets secret.
"People would be pissed if someone else leaked something," explained one former employee. "You don't betray the family."
Company-wide Q&As aren't unique to Facebook. They have become standard in the tech industry, a tradition that many trace back to Google and its weekly all-hands meetings, called TGIF. Twitter, Uber and Nextdoor hold them, too.
But Zuckerberg's celebrity and Facebook's size and influence make the company's weekly ritual rather astonishing. Zuckerberg has even started doing public Q&As with Facebook users in different cities around the globe.
Some believe Zuckerberg gets as much out of the events as his employees. The meetings offer Zuckerberg a chance to hear from the rank and file, but also a chance to improve his public speaking skills. (Zuckerberg was a notoriously poor and awkward public speaker in the company's early days, but has improved dramatically over the years.)

At Facebook headquarters, the Q&As work like this:
Each Friday at 4 pm PT, Zuckerberg speaks for about an hour from the cafeteria in Facebook's massive new building in Menlo Park. Zuckerberg's top lieutenants — folks like COO Sheryl Sandberg, product boss Chris Cox and CTO Mike Schroepfer — sit in the front row of chairs set up for employees in case Zuckerberg wants to call on them to answer a question.
The meetings are usually limited to Facebook employees, though others have made appearances, too. Board members Peter Thiel, Susan Desmond-Hellmann and Don Graham have all attended Q&As, as did Jay Z back in the summer of 2013, though no one seems to remember why he was there. If you work out of a remote Facebook office, the Q&As are streamed live and then uploaded to Facebook's internal portal for a short time so people can watch them at their convenience.
Zuckerberg starts with opening remarks, then typically acknowledges any long-tenured employees celebrating a work anniversary that week — what Facebookers call a "Faceversary." If you've been there long enough, usually around a decade, you might get to go up and share a favorite story about your time with Facebook.
Then Zuckerberg highlights a "fix of the week," usually honoring some behind-the-scenes engineering fix or accomplishment that others may not be aware of. It's a small shout-out that's meant to help Facebook keep its "hacker DNA," even as the company swells in size.
Then Zuckerberg highlights a "fix of the week," usually honoring some behind-the-scenes engineering fix or accomplishment that others may not be aware of. It's a small shout-out that's meant to help Facebook keep its "hacker DNA," even as the company swells in size.
After the formalities, Zuckerberg digs into questions submitted by employees, starting with the most popular questions Facebookers have submitted and voted on throughout the week using an internal Facebook group. (The questions aren't submitted anonymously.) A snapshot of this polling system published by Gizmodo earlier this year showed questions ranging from Snapchat's business strategy to whether or not employees should try to stop Donald Trump's presidential campaign.
Once the poll questions are done, Zuckerberg will take unfiltered questions from the audience for the remainder of the time.
Topics vary wildly. Zuckerberg usually won't comment publicly on competitors, but at Facebook Q&As, he'll talk candidly about Twitter and Snapchat. He's talked about Elon Musk and his rocket ambitions on multiple occasions. When Kanye West asked Zuckerberg for $1 billion on Twitter, Zuckerberg was inevitably asked about it the following Friday. "Maybe if he'd asked me on Facebook," one employee remembered him joking.
The questions and ensuing responses can also get serious. Zuckerberg took issue when board member Marc Andreessen compared the company's Internet.org initiative in India to colonialism, and once gave an impassioned speech about the Black Lives Matter movement after an internal note he sent around to the company was published online.
Usually, though, Zuckerberg is relaxed. And seeing a relaxed and authentic version of Zuckerberg is one of the reasons employees still look forward to hearing from their CEO, and why they're so tight-lipped about what he has to say.
"It's a side of Mark Zuckerberg that the outside world doesn't have access to," one former employee explained.
But that dedication to Zuckerberg appears to be under some pressure. Since the 2016 election, we've seen some uncharacteristic dissent among Facebookers, most notably when a small band of employees started their own task force to investigate Facebook's role in disseminating fake news leading up to the election. That move, breaking company message and openly defying Zuckerberg, was shocking to numerous former employees we spoke to.
Whether or not that's an isolated incident or just the nature of a company growing up, will undoubtedly come back to Zuckerberg.
"People come to work at Facebook because they want to work for Zuckerberg," said one former employee. "No one else has a Mark."
This piece originally appeared on recode.
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