OpenAI signs SF's largest office lease since 2018

While Big Tech spent the last two years desperately subleasing empty office floors, OpenAI just did the exact opposite.

An Uber spokesperson confirmed on Friday that OpenAI has officially leased two entire buildings at Uber's Mission Bay headquarters in San Francisco. The deal covers 1455 and 1515 Third Street, totaling nearly half a million square feet.

First reported by the San Francisco Chronicle, the lease marks the single largest office real estate transaction in San Francisco since 2018.

Room for two thousand engineers

A nearly 500,000-square-foot footprint is no small commitment. In tech real estate terms, that is enough desk space to house an expansion of more than 2,000 employees.

The massive sublease comes at a critical moment for the city. After years of post-pandemic tech layoffs and remote work adoption, tech heavyweights like Facebook, Salesforce, and LinkedIn flooded the market with sublease inventory.

According to commercial real estate firm CBRE, San Francisco's office vacancy rate recently touched an astonishing 34%. OpenAI's move represents a sudden throwback to the pre-pandemic tech boom.

San Francisco Mayor London Breed celebrated the deal, pointing out that OpenAI is choosing to grow in the very city where it was born.

The gravity of Area AI

OpenAI is hardly alone in grabbing physical territory in the city.

Over the past several months, Anthropic, Hive AI, Hex, and a string of other artificial intelligence startups have taken down space across San Francisco. Most are clustering within a zone dubbed Area AI, which spans Potrero Hill and Showplace Square.

These rapid expansions have provided a lifeline to a commercial property market that many feared was entering a long-term doom loop. OpenAI did not immediately respond to requests for comment regarding the lease.

Why it matters

This is not just a commercial real estate story; it is a major declaration of intent from the frontrunner of the AI boom.

First, it signals where generative AI development is actually happening. While traditional software companies trimmed staff and embraced fully remote setups, OpenAI is betting heavily on in-person collaboration. Packing 2,000 people into adjacent campus buildings suggests the company believes high-friction, rapid-fire model training and product iteration require people sharing the same physical room.

Second, it cements San Francisco as the undisputed epicenter of artificial intelligence. Critics spent years predicting the demise of the Bay Area tech scene due to local governance, high taxes, and public safety issues. But when Anthropic and OpenAI decide to anchor their largest footprints in Mission Bay, every tier-one researcher and founder has to take note.

There is, however, real financial risk here. Nearly half a million square feet carries massive recurring overhead. If OpenAI's explosive enterprise revenue slows down or compute infrastructure costs cannibalize operating margins, managing a sprawling physical footprint could quickly turn from a victory lap into a severe drag on cash flow.