AI Firm Anthropic Leases Entire Downtown SF Office Building

The tech company's major expansion in the city comes as many firms cut office space.

Jan. 30, 2026 at 12:47pm by Ben Kaplan

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Anthropic, a leading artificial intelligence company, has signed a deal to occupy the entire 420,000-square-foot office building at 300 Howard Street in downtown San Francisco. This represents one of the largest single-tenant office leases in the city since the pandemic began. The move is both an expansion and consolidation for Anthropic, which has grown rapidly from a small startup into a prominent player in the AI industry. The company now employs over 2,500 people globally and has seen its revenue skyrocket in recent years.

Why it matters

Anthropic's decision to significantly expand its footprint in downtown San Francisco is seen as a potential inflection point for the city's core, which has struggled with high office vacancy rates during the pandemic. The move stands in contrast to the broader corporate migration away from the city, as many tech companies have cut office space or relocated to lower-cost areas. Anthropic's growth and commitment to San Francisco is viewed as an encouraging sign for the city's economic recovery.

The details

Anthropic has already occupied 230,000 square feet at 500 Howard Street for its headquarters since 2023, and in September agreed to lease an additional 100,000 square feet at 505 Howard Street. The new 300 Howard Street lease will consolidate the company's operations into a single, larger building. The property was previously occupied by Fitbit and StubHub but has struggled to attract major tenants in recent years. The building's new owners, DivcoWest and Blackstone, renovated the property to appeal to modern tenants.

  • Anthropic has occupied 230,000 square feet at 500 Howard Street since 2023.
  • Anthropic agreed to lease 100,000 square feet at 505 Howard Street in September.
  • Anthropic signed the 13-year lease for the entire 420,000-square-foot 300 Howard Street building in January 2026.

The players

Anthropic

An artificial intelligence company that has grown rapidly from a small startup into one of the most prominent players in the AI industry. Anthropic was founded in 2021 by San Francisco natives and siblings Dario and Daniela Amodei, who previously worked at OpenAI.

Dario Amodei

Co-founder of Anthropic and a San Francisco native who attended Lowell High School.

Daniela Amodei

Co-founder of Anthropic and a San Francisco native who attended Lowell High School.

DivcoWest

A real estate investment firm that acquired the 300 Howard Street building in 2025 and renovated it to appeal to modern tenants.

Blackstone

A global investment firm that partnered with DivcoWest to acquire the 300 Howard Street building in 2025.

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What they’re saying

“Dario and I were born and raised in San Francisco — it's where Anthropic was founded, and where so much of our story has unfolded. With over 1,300 employees in the Bay Area and counting, I'm especially excited about what this growth means for the local community as we look to deepen our partnerships with the incredible businesses and organizations doing meaningful work in the city that we love and call home.”

— Daniela Amodei, Co-founder, Anthropic (San Francisco Chronicle)

What’s next

Anthropic's expansion into the 300 Howard Street building is expected to provide long-term capacity for the company's rapidly growing workforce, which now exceeds 2,500 employees globally.

The takeaway

Anthropic's decision to significantly expand its presence in downtown San Francisco, at a time when many tech companies are cutting office space, is seen as an encouraging sign for the city's economic recovery. The move highlights San Francisco's continued appeal as a hub for leading technology companies and signals Anthropic's commitment to the local community.