Ozy Media’s chairman resigns as company faces questions.

The chairman of the Ozy Media board resigned on Thursday, saying he lacked the experience in “crisis management and investigations” to continue leading the company.

Marc Lasry, a hedge fund manager who is also a co-owner of the Milwaukee Bucks, made the announcement four days after The New York Times reported that someone from Ozy appeared to have impersonated a YouTube executive during a conference call with Goldman Sachs bankers while trying to raise $40 million dollars.

Ozy’s chief executive, Carlos Watson, told The Times that the person had been Samir Rao, the company’s co-founder and chief operating officer. During the call, the supposed YouTube executive praised Ozy, saying it was a great success on the platform. Mr. Watson attributed the incident to a mental health crisis. Mr. Rao has not replied to questions about his role on the call.

“I believe that going forward Ozy requires experience in areas like crisis management and investigations, where I do not have particular expertise,” Mr. Lasry said in an emailed statement. “For that reason, I have stepped down from the company’s board. I remain an investor in the company and wish it the best going forward.”

Ozy, which made its debut in 2013, presents itself as a popular millennial media company. It investors have included Emerson Collective, the organization run by Laurene Powell Jobs, and Axel Springer, the publishing giant based in Berlin. Ron Conway, a Silicon Valley investor and an early Ozy backer, said this week that he had returned his shares to the company.

On Tuesday, the Ozy board said it had hired the law firm Paul, Weiss, Rifkind, Wharton and Garrison to investigate the company’s “business activities” and leadership team.