Sheryl Sandberg, COO of Meta, Facebook's parent company, announces she's leaving

Sheryl Sandberg, the COO of Meta, Facebook's parent company, announced Wednesday she is stepping down from her position with the company. She had held the role since 2008.

"Sitting by Mark's side for these 14 years has been the honor and privilege of a lifetime," Sandberg wrote in a post on Facebook announcing the decision.

She and CEO Mark Zuckerberg will work to transition her responsibilities over the summer and officially hand off the role in the fall. She will continue to serve on the board of directors.

Javier Olivan, Meta's vice president of central products, will take over the COO role.

Sandberg, a former Google executive who helped optimize that company's ad business, joined Facebook when the social media platform still lacked a "like" button.

She led a dramatic increase in Facebook's revenue by revamping its advertising business, turning the operation into an industry powerhouse that helped small and large businesses target users through data collected by the platform.

In 2007, the year before Sandberg arrived, the company's revenue barely exceeded $150 million. Last year, the company brought in about $117 billion.

Meta has faced public scrutiny and legal challenges over its business operations.

In December 2020, the Federal Trade Commission sued Meta over allegedly sustaining a monopoly through anticompetitive practices. In January, a federal judge allowed the lawsuit to proceed past a procedural hurdle.

A separate lawsuit, filed by state attorneys general in December as well, accuses Facebook of colluding with Google to dominate the online advertising business.

Facebook has challenged the allegations in both lawsuits.

"The debate around social media has changed beyond recognition since those early days," Sandberg wrote. "To say it hasn't always been easy is an understatement. But it should be hard. The products we make have a huge impact, so we have the responsibility to build them in a way that protects privacy and keeps people safe."

Sandberg is also the chair of the board of directors at the Sheryl Sandberg and Dave Goldberg Family Foundation, which she established in 2013. The organization focuses its work on empowering women in the workplace as well as helping individuals and communities build resilience.

In the announcement on Wednesday, Sandberg said she plans to devote more time to the foundation.

"I am not entirely sure what the future will bring – I have learned no one ever is," she wrote. "But I know it will include focusing more on my foundation and philanthropic work, which is more important to me than ever given how critical this moment is for women."

ABC News' Mary Kathryn Burke contributed to this report.