Washington, DC. (AP) — TikTok CEO Shou Zi Chew testified Thursday at a congressional hearing over concerns about user data collected by the popular video-sharing app and potential Chinese spying.

Under his helm, TikTok reached 150 million users in the U.S., the majority of them teens and young adults who are attracted to the app’s simple interface and addictive algorithm that serves up short videos on just about any imaginable topic.

Lawmakers have said they’re worried about American data falling into the hands of the Chinese government and claim it threatens national security and user privacy and could be used to promote pro-Beijing propaganda and misinformation.

Chew attempted to persuade lawmakers not to pursue a ban on the app or force Chinese parent company ByteDance to give up its ownership stake, testifying that TikTok prioritizes the safety of young users. He says the company plans to store all U.S. user data on servers maintained and owned by the software giant Oracle.

Here’s a closer look at Chew:

WHAT IS HIS BACKGROUND?

Chew, 40, is a native of Singapore, where he lives with his wife, Vivian Kao, and their two children. He graduated in 2006 from University College London and worked for two years at Goldman Sachs before moving to the U.S. to pursue a master’s degree at Harvard Business School. Chew had a two-year internship with Facebook.

After earning his MBA, he became a partner at venture capital firm DST Global, where he worked for five years and helped facilitate investment in the company that became ByteDance. He then worked for five years at Xiaomi, a Chinese smartphone company, before being appointed TikTok CEO in 2021, replacing Kevin Mayer, a former Disney executive. Chew reports to ByteDance CEO Liang Rubo.

WHAT’S HIS REPUTATION?

The U.S. public knows relatively little about Chew compared with Silicon Valley social media giants such as Facebook’s Mark Zuckerberg, said Brooke Erin Duffy, who studies social media platforms as an associate professor of communications at Cornell University.

“Chew has been in the background on public discourse until now, so he doesn’t have the same reputation we would associate with the Silicon Valley set, especially Zuckerberg,” Duffy said.

Most Americans likely first heard of Chew when he released a video this week speaking directly to TikTok’s U.S. users, she said, “so he doesn’t have the same reputation as someone we know, and (we) don’t have sense of who he is.”

But Chew is well-respected within the U.S. and China tech communities, and was considered a good fit for TikTok because of his background in investment banking and his time at Facebook and DST Global, said Dan Ives, managing director of New York-based Wedbush Securities.

“He gained a lot of respect just by taking that high risk, in-the-hot seat role at TikTok,” Ives said, adding that the company likely thought he was the right person to ease tensions with U.S. lawmakers.

HOW DID HE DO IN HIS TESTIMONY?

Chew’s decision to emphasize TikTok’s reach in the U.S. might have backfired, and “actually strengthened U.S. lawmakers’ argument that TikTok poses a threat to both national security and young people,” said Jasmine Enberg, a social media analyst at Insider Intelligence.

Enberg said there was little Chew could say to convince lawmakers that TikTok is not monitored or influenced in some way by the Chinese government.

Ives said Chew’s testimony was always going to be fraught, but his lack of concrete answers about data access and security was “a disaster” and likely set the stage for a ban.

“It was a perfect storm and lawmakers were ready,” Ives said.

But Shelly Palmer, a professor of advanced media at Syracuse University who studies social network business models, said Chew did the best he could given the grilling he received from lawmakers who “in my opinion were not actually listening” but instead were grandstanding.

“I don’t think he has the ability, because of who he is and what he does, to be satisfying to this audience,” said Palmer, adding that he believed Chew’s answers were not unlike those given by CEOs from U.S.-based social media companies who have been questioned in the past about privacy.