In a period of doom and gloom for the commercial real estate sector, hammered by remote work and high vacancy rates in cities across the U.S., the deal offers a dose of hope. And for San Francisco, whose struggles with crime and homelessness have been well documented, it adds to a growing presence of companies involved in the burgeoning field of artificial intelligence. 

Since kickstarting the AI boom with the release of ChatGPT last year, OpenAI has quickly become one the world’s most valuable closely held companies. Bloomberg reported earlier this month that OpenAI is in talks to sell shares an $86 billion valuation, and it reported in August that the company is on track to generate $1 billion in annual revenue.

OpenAI is leasing two buildings from Uber, which is “right-sizing” its real estate usage, at the ride-hailing company’s headquarters campus in the Mission Bay neighborhood. An Uber spokesperson confirmed to Fortune that the deal had finally closed. (Since it’s a sublease, landlords had to give their consent, which meant longer negotiations.) OpenAI is taking 486,600 square feet in all in the four-building campus.

As the Wall Street Journal reported earlier this month, office attendance in large cities is still only about half the level seen in 2019. That’s despite a slight uptick recently and tough talk from high-profile CEOs about enforcing return-to-office policies.

As for San Francisco, it notched a record-high 33.9% office vacancy rate—nearly 30 million square feet listed for lease or sublease—in the third quarter, as reported by the San Francisco Chronicle. The paper noted that about 150,000 workers could fill all the empty office space.

The lack of all those employees hurts local businesses, including retailers and restaurants. That combined with the crime problem has prompted companies to give up on the city. In August, one of the city’s flagship retailers, Nordstrom, closed its once-vibrant store.

As the owner of the mall that Nordstrom inhabited noted, “A growing number of retailers and businesses are leaving the area due to the unsafe conditions for customers, retailers, and employees, coupled with the fact that these significant issues are preventing an economic recovery of the area.” 

The city’s “doom spiral” fears continue, but the move by OpenAI provides a bit of hope. And it helps that this year other AI firms have also leased office space in San Francisco.

As the Chronicle reported, Hive AI leased 57,117 square feet in a downtown skyscraper next to Salesforce Tower. Hayden AI leased 41,196 square feet, Anthropic leased 17,735, and Tome AI 16,887. (On Friday, Google said that it’s agreed to invest up to $2 billion in Anthropic, following Amazon saying it will invest up to $4 billion.)

That means five AI companies, including OpenAI, are leasing nearly 620,000 square feet of office space in the city. Of course, that’s still a drop in the bucket compared to amount of vacant space. 

“There’s definitely a lot of hope and optimism that [AI] could be the catalyst for the next growth cycle not only for the office market, but for the San Francisco economy,” Colin Yasukochi, executive director of CBRE’s Tech Insights Center, told the Chronicle. But it could be years before “we see this growth cycle really explode,” if it does at all, he noted.

As it turns out, OpenAI’s office deal closed just as another San Francisco tech company ended a return-to-office experiment. Expensify, with a market cap of about $215 million, said this week that it’s closing an upscale office lounge where employees could enjoy champagne or a draft beer while collaborating in a restaurant-style booth or working on laptops at the bar.

In a blog post this week, Expensify CEO David Barrett described the lounge as an experiment on luring employees back into the office, and he concluded that remote work had won. “We’re just never going back to a regular nine-to-five office culture, a staple of not just our modern culture, but also the foundation of most urban planning,” he wrote. 

For his part, OpenAI’s Altman—who has become a household name in the tech world and perhaps beyond—stressed the need for in-person collaboration and noted the shortcomings of remote work during a Stripe conference in San Francisco earlier this year. 

“I think definitely one of the tech industry’s worst mistakes in a long time was that everybody could go full remote forever, and startups didn’t need to be together in person and, you know, there was going to be no loss of creativity,” he told attendees. “I would say that the experiment on that is over, and the technology is not yet good enough that people can be full remote forever, particularly on startups.”

OpenAI did not immediately reply to Fortune’s request for comments.