Anthropic expands in Seattle as AI boom offers hope for struggling office market

Anthropic is embarking on a major expansion in Seattle, underscoring how artificial intelligence companies are emerging as one of the few bright spots in the region’s office market.

The maker of the Claude AI model recently finalized a lease at Dexter Yard North in Seattle’s South Lake Union neighborhood, capping months of speculation about the company’s expansion plans in the region.

Terms of the deal were not publicly disclosed, but CoStar News reports that the company leased 113,000 square feet of space across multiple floors in the north tower at 700 Dexter Avenue North. CoStar called it one of the largest office deals of the year so far in Seattle.

The expansion would significantly increase Anthropic’s footprint in Seattle, where the San Francisco-based company established an engineering office in 2024 as it recruited talent from the region’s deep pool of AI researchers and software engineers.

It would also place Anthropic next door to Amazon. The companies in April expanded their existing partnership: Amazon committed to invest up to $25 billion in Anthropic, which simultaneously made a $100 billion-plus spending commitment to AWS over 10 years. 

The following month, Anthropic announced $65 billion in funding at a $965 billion valuation, thought to be the last venture round before an initial public offering later this year.

On Thursday, Anthropic released Claude Sonnet 5, which the company says “can make plans, use tools like browsers and terminals, and run autonomously at a level that, just a few months ago, required larger and more expensive models.”

Also this week, The U.S. Department of Commerce removed export controls on the company’s Claude Fable 5 and Mythos 5 models, part of an ongoing back-and-forth with the Trump administration.

Anthropic’s Seattle lease provides hope that demand from AI companies could help revive parts of Seattle’s office market after several years of elevated vacancy driven by remote work and tech industry cutbacks. Seattle’s office vacancy rate inched up to 28% during the first quarter, the highest in the region.

Other AI firms, including OpenAI and Databricks, have also expanded their Seattle-area office footprints in recent months. In those instances, the companies chose to grow in nearby Bellevue.

Dexter Yard, a two-building office and life sciences campus developed by BioMed Realty, opened in 2022 and was designed to accommodate both technology and biotech tenants. The north tower contains approximately 163,000 square feet of office and lab space.

Anthropic has a number of open engineering roles spread across Seattle, New York and San Francisco. The company says it expects all staff to be in one of their offices at least 25% of the time.

A spokesperson for Anthropic acknowledged the new lease, but did not respond to requests for additional comment.