Twitter Inc’s Chief Operating Officer Anthony Noto has resigned to join online lender Social Finance Inc (SoFi) as its chief executive officer.

His departure comes at a time when the social media company is in the middle of a turnaround plan, sending the shares of the owner of microblogging site down as much as 3.9 percent.

After leading Twitter’s successful IPO in 2013 as a Goldman Sachs banker, Noto joined the company the next year as its chief financial officer.

In 2016, he replaced Adam Bain as COO to lead Twitter’s business and revenue generating operations when Bain quit.

“Anthony has been an incredible advocate for Twitter and a trusted partner to me and our leadership team,” Twitter CEO Jack Dorsey said in a statement.

MKM Partners’ analysts said investors would consider the departure a meaningful blow to Twitter’s turnaround plans.

Analysts at SunTrust Robinson said Noto’s exit is a major loss for the company as he was responsible for the company’s strategy to sign video deals with the likes of Buzzfeed and National Football League.

Noto will join SoFi as its CEO and director from March 1, the online lender said, adding that interim CEO Tom Hutton, who also has been serving as executive chairman, will become non-executive chairman.

SoFi’s plans to go for an initial public offering, according to media reports, could get a boost from Noto’s experience in handling IPOs.

In September, the online lender’s former CEO Mike Cagney had to step down after the San Francisco-based company launched a probe into claims of sexual harassment at work by current and former employees.

Shares of Twitter were down 2.1 percent at $22.82 in morning trading. It had risen nearly 41 percent in the last 12 months.