Sheryl Sandberg’s announcement that she would not stand for reelection to the Meta board in May was, in many ways, the last step in her long exit from the company. While she’ll stay on as an adviser and said she will “always be there to help the Meta teams,” the days of her outsize level of influence at the company are seemingly at an end.

Founder and CEO Mark Zuckerberg, of course, is the person whose opinion matters most at Meta. He controls more than 50% of the total voting power at the company, giving him a de facto veto over both investors and his own board. But even Zuck can’t grow a company to a $980 billion market cap on his own.

With Sandberg’s looming departure, here’s a look at the top lieutenants at the social media giant—and what they do.

JAVIER OLIVAN

As chief operating officer at Meta, Olivan oversees the business teams, the infrastructure, and central products. He’s been with Meta since 2007 and formerly served as chief growth officer, where he was responsible for Facebook’s user increases. Several companies have reportedly tried to hire him away, but he has remained loyal to Meta and Zuckerberg. Sandberg singled out his leadership, along with that of two other execs, in her post.

JUSTIN OSOFSKY

Osofsky also received a mention from Sandberg, which might seem unusual, as he’s not a direct report of Zuckerberg and not an especially public figure. As head of online sales, operations, and partnerships, though, the former chief operating officer at Instagram oversees revenue and engagement, with a focus on growing the number of small- and medium-size businesses that use the platforms. He also oversees the Content Partnerships team, which is the group that puts personalized content into your feeds on Facebook and Instagram.

NICOLA MENDELSOHN

As head of Meta’s global business group, Mendelsohn is responsible for maintaining relationships with the top marketing companies and ad agencies. And if you doubt how important that position is, consider the situation at X (formerly Twitter), which saw a revolt from those sorts of companies earlier this year after Elon Musk seemingly endorsed an antisemitic tweet, then lashed out at advertisers after they pulled back their business.

NICK CLEGG

Once the deputy prime minister of the U.K., Clegg is now president of global affairs for Meta. That puts him in charge of all policy matters as the company faces an increasing amount of global regulation, an extremely powerful position. His decisions affect the users of all Meta properties.

“Nick will now lead our company on all our policy matters, including how we interact with governments as they consider adopting new policies and regulations, as well as how we make the case publicly for our products and our work,” Zuckerberg wrote when announcing the promotion in 2022.

ADAM MOSSERI

Mosseri, with his semifrequent announcement videos, might be the most well-known name on this list among users. He became head of Instagram when the founders of that app resigned in 2018—and he’s unofficially in charge of Meta’s Twitter/X competitor Threads. It’s quite a journey from his beginnings at the company in 2008, where he started as a product designer. Among his many responsibilities are keeping Meta competitive with TikTok and overseeing the safety of teenagers who use Instagram, something for which the company has regularly come under fire.

ANDREW BOSWORTH

Better known as “Boz” in the tech world, Bosworth was a teacher at Harvard while Zuckerberg was a student. After joining Meta in 2006, he created one of the first AI systems, which, essentially, created the news feed on Facebook. Today, he’s chief technical officer, and he’s had his hand in pretty much every corner of the organization. Much of his time currently is spent with the Reality Labs unit, where he oversees efforts in augmented and virtual reality, including the Quest VR headset

CHRIS COX

Cox, for years, worked alongside Boz, but this week, the product chief was tapped to oversee Meta’s AI efforts. Zuckerberg announced a reorganization that saw the chief AI scientists reporting to Cox, instead of Bosworth. It’s quite a move for the former No. 3 executive, who left Facebook in 2019 after the company’s privacy pivot. He returned the next year and now is front and center in what is arguably the most important growth area of the company.