After weeks of Mission Bay residents and businesses waiting with bated breath, one of the largest office deals of the year just closed in San Francisco.

An Uber spokesperson confirmed Friday morning that ChatGPT maker OpenAI is leasing out two buildings from its Mission Bay headquarters—1455 and 1515 Third St.—a deal that will further entrench the emergent artificial intelligence giant into San Francisco.

The news was first reported by the San Francisco Chronicle. 

The deal, which has been in the rumor mill for months, amounts to nearly a half-million square feet of space that OpenAI will be taking over. It represents the largest office lease in San Francisco since 2018, a time when large tech companies were taking spaces across the city in expectation of continuing growth.

The pandemic put a pause on many of those plans amid industry layoffs and a shift to remote work structure. Many large tech employers put up wide swaths of their San Francisco office space on the sublease market, including Facebook, Salesforce and, recently, LinkedIn.

But OpenAI's lease is a throwback to those boom times for a growing industry that many San Francisco leaders have rested their hopes on. The new space will provide room for the company to expand to more than 2,000 employees.

Mayor London Breed, who’s been a big booster of the artificial intelligence industry’s presence in “the AI capital of the world,” celebrated the deal. 

“OpenAI is at the forefront of an industry that is transforming the world, and I am proud they are expanding right here in San Francisco where they first started,” Breed said in a statement. “This major investment and commitment to our city sends a message that this city is the place to be if you want to be a part of what’s next.”

Already, Anthropic, Hive AI, Hex and a slew of other startups have taken on new spaces in San Francisco in recent months—many of them within a radius of “Area AI,” which includes Potrero Hill and Showplace Square. It’s served as a balm to the city’s ailing office market, which recently reached a stunning 34% vacancy rate, according to a report from real estate firm CBRE. 

An OpenAI spokesperson did not immediately respond to a request for comment.