Twitter chief operating officer Adam Bain is stepping down.
Bain, who oversaw the social network's ad business, announced the move Wednesday on Twitter. "I have nothing but love for this unbelievable company & product," he tweeted. "It's been a privilege to have played a role in helping build something so special."
Anthony Noto, Twitter's chief financial officer, will take over responsibilities for ad sales and assume the role of COO while Twitter begins a search for a new CFO.
"Since joining Twitter in 2010, Adam has built an amazing team and a global business from the ground up," Twitter CEO Jack Dorsey said in a statement. "I'm grateful to Adam for everything he's done for Twitter, and for his leadership and friendship over the years. I can't wait to see what he does next!"
Bain's departure comes as Twitter has struggled to reignite ad sales growth amid slowing growth of its user base and an increasingly challenging digital advertising market.
Meanwhile, Noto has been behind much of Twitter's new focus on live video, spearheading such deals as its agreement to live stream a package of the NFL's Thursday Night Football games.
"Anthony is a passionate leader who has shown an unmatched depth of financial expertise as our CFO," said Dorsey. "He's also a stellar operational leader, and consistently shows a capacity to take on more. Anthony's leadership as our COO combined with Matt's proven track record leading global sales gives us confidence as we drive towards our goal of GAAP profitability in 2017 to ensure Twitter continues to serve more and more people."
Added Noto: "I am honored by the trust that Jack has placed in me to take on this new role. I've enjoyed nothing more than partnering every day with Adam in striving to achieve Twitter's goals, and I will always be grateful for his tremendous contributions. I look forward to leading this team and capitalizing on our recent momentum of accelerating audience and engagement metrics."
Last month, Twitter held talks with a number of potential suitors about the possibility of a sale, but a deal did not materialize. During its third-quarter earnings at the end of October, Dorsey would not comment on the takeover speculation but said he was "committed to maximizing shareholder value." Twitter also announced that it would cut 350 jobs, or about 9 percent of its workforce, to make it a leaner operation.
Twitter shares were down more than 3 percent during after-hours trading on the news of Bain's departure.