RIYADH, Saudi Arabia — This week, as Saudi Arabia held its annual investment conference in Riyadh, a boisterous event that attracts business leaders and political officials from around the world, the big mystery was what happened to the host.
Yasir al-Rumayyan, the Saudi official who oversees the kingdom’s $450 billion sovereign wealth fund, was missing from the annual investment conference he typically presides over.
He did not deliver opening remarks in the conference ballroom, as he had been scheduled to do, and he did not show up at a panel discussion with the chief executives of Goldman Sachs and the money management company BlackRock.
He was even absent from the week’s signature evening get-together: an opulent dinner for scores of event speakers at his home in Riyadh, the capital.
The organizers of the event, the Future Investment Initiative, referred questions about Mr. al-Rumayyan’s absence to the Saudi government. Kevin Foster, the Public Investment Fund’s global head of communications, did not respond to a request for comment.
There is likely a mundane explanation. Four attendees with close ties to Mr. al-Rumayyan said that he had been diagnosed with Covid-19, an account that was widely whispered about in sideline conversations at the conference. The New York Times could not confirm those reports.
But the lack of an official explanation inadvertently highlighted one of the biggest concerns investors have with the Saudi fund.
By not acknowledging Mr. al-Rumayyan’s sudden absence from an event intended to demonstrate Saudi investment and growth, the fund only reminded investors that it still operates according to its own rules — under which transparency is not always a priority.
“Every organization is struggling with how to be present, how to be visible, and then these things happen,” said Karen E. Young, a senior fellow at the Middle East Institute, a research institute in Washington that focuses on American relations with the Middle East. “I think it’s where we all are, unfortunately. Sometimes government and government entity communications, they don’t necessarily always go smoothly with each other.”
The Public Investment Fund, which is led by Saudi Arabia’s effective ruler, Crown Prince Mohammed bin Salman, wants to be taken seriously internationally.
In addition to its raft of investments in Saudi Arabia, it is a major investor in a variety of international entities. Those include Uber, where Mr. al-Rumayyan is a board member, the electric vehicle company Lucid Motors and a large infrastructure investment fund at Blackstone, the private equity firm.
The fund has cast itself as a global leader in governance and transparency. But some companies worry about investing in a country that has committed human rights atrocities, and many analysts doubt that there is really a wall between the fund and the royal family.
After a surge of coronavirus cases last year, Saudi Arabia has turned the numbers around with a relatively high vaccination rate and low case numbers, according to the World Health Organization. The government requires proof of vaccination for international travelers.
Mr. al-Rumayyan, who is the public face of the kingdom’s increasingly global network of investments, has had a particularly busy travel schedule lately.
On Oct. 17, he sat in the owner’s box of the St. James’s Park soccer stadium in Newcastle, England, where he was cheered by fans. He wore a black-and-white scarf bearing the logo of Newcastle United, the Premier League soccer team that the Public Investment Fund recently bought a stake in, making him the club’s new chairman.
Two days later, he shook hands with Queen Elizabeth at the Global Investment Summit at Windsor Castle, an event meant to emphasize green technology and finance investment opportunities in Britain. After that, he traveled to Washington, D.C., where he received a leadership award at a 75th-anniversary event for the Middle East Institute.
Despite his absence, the investment summit, which ended Thursday, has run smoothly. Thousands of attendees gathered at the Ritz-Carlton and its adjoining conference center to watch the discussion panels and technology showcases, mingling and sipping coffee and nibbling on pastries between sessions.
On Tuesday, Prince Mohammed made a surprise appearance. He did not speak, but he received a standing ovation.