Sheryl Sandberg Is Stepping Down from Meta, Says It's 'Time to Write the Next Chapter of My Life'

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Sheryl Sandberg is stepping down as the Chief Operating Officer of Meta, 14 years after she joined the Facebook parent company.

The 52-year-old made the announcement in a post on her Facebook page Wednesday, explaining she plans to leave the company this fall but will remain on its board of directors.

"When I took this job in 2008, I hoped I would be in this role for five years. Fourteen years later, it is time for me to write the next chapter of my life," Sandberg wrote in the post, adding that she plans to marry her partner, Tom Bernthal, this summer.

"I am not entirely sure what the future will bring — I have learned no one ever is," she added.

Sandberg said she plans to focus on philanthropy and her work with Lean In, her nonprofit that provides a support network for women. She will also work with Meta co-founder Mark Zuckerberg to transition her responsibilities before her departure.

Listen below to an interview with Sheryl Sandberg on our daily podcast PEOPLE Every Day.

"I am so immensely proud of everything this team has achieved," the Option B author said. "The businesses we've helped and the business we've built. The culture we've nurtured together."

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Matt Winkelmeyer/Getty Sheryl Sandberg

"And I'm especially proud that this is a company where many, many exceptional women and people from diverse backgrounds have risen through our ranks and become leaders — both in our company and in leadership roles elsewhere," she continued.

Sandberg — who previously worked at Google — ended her announcement by thanking her colleagues and Zuckerberg, whom she called "one of the best friends anyone could ever have."

In a separate post, Zuckerberg, 38, called Sandberg someone who "cares deeply about the people in her life" and is "generous about nurturing relationships and helping you grow as a person."

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"She has taught me so much and she has been there for many of the important moments in my life, both personally and professionally," he said. "Whether going through the different transitions we've made as a company over the years, or when she supported me and [wife] Priscilla [Chan] as we navigated challenges having children, our partnership has always been deeper than just business."

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"I'm sad that the day is coming when I won't get to work as closely with Sheryl," he added. "But more than anything, I'm grateful for everything she has done to build Meta. She has done so much for me, for our community, and for the world — and we're all better off for it."

Zuckerberg said Javier Olivan, Meta's Chief Growth Officer, will replace Sandberg as COO. He added that Olivan's position will be a "more traditional" COO role.