Linda Yaccarino on Wednesday said she's stepping down as CEO of X, formerly known as Twitter, after a two-year tenure.

"When Elon Musk and I first spoke of his vision for X, I knew it would be the opportunity of a lifetime to carry out the extraordinary mission of this company," she posted on the platform.

"I'm immensely grateful to him for entrusting me with the responsibility of protecting free speech, turning the company around, and transforming X into the everything app," she said.

Yaccarino hired by Musk after he bought Twitter 

Yaccarino was a former head of advertising at NBCUniversal Media before she was hired by Musk in May 2023. 

Musk bought Twitter in a controversial takeover for $44 billion in late 2022, cut most of its staff and rolled back content moderation policies.

Musk said said at the time that Yaccarino's role would be focused mainly on running the company's business operations, leaving him to focus on product design and new technology.

"Thank you for your contributions," Musk wrote on X in response to Yaccarino's announcement.

Musk mired in controversy 2 years since takeover

Ever since buying Twitter and rebranding it to X, Musk has faced several challenges on the platform, including bringing back advertisers who fled over concerns that thinning content moderation policies were allowing hate speech to flourish. 

In 2023, for example, Musk sparked a wave of backlash after a left-leaning media watchdog said it found ads for major companies placed alongside neo-Nazi and white nationalist posts.

On Wednesday, Musk's artificial intelligence company, xAI, said it was working to remove "inappropriate posts" on X after its chatbot, Grok, shared multiple antisemitic comments.

Musk announced earlier this year that xAI had acquired X.

"Now, the best is yet to come as X enters a new chapter with xAI," Yaccarino wrote. "I’ll be cheering you all on as you continue to change the world."

Edited by: Wesley Rahn