Count it in acres and the number is abstract. Count it in football fields and it lands: Anthropic, a company that did not exist five years ago, has signed leases on approximately 1.6 million square feet of office space — about twenty-eight American gridirons including the end zones, or nineteen Premier League pitches laid end to end. Nearly all of it was committed within the past eighteen months.
The company employs somewhere north of 2,500 people globally. On paper, that is roughly 640 square feet per head, a ratio that would have made a pre-pandemic corporate real estate director choke on his coffee. Anthropic is not leasing for the workforce it has. It is leasing for the one it expects.
Anthropic's San Francisco footprint now approaches a million square feet, concentrated so densely along a two-block stretch of Howard Street that local brokers have taken to calling it Anthropic Row.
The company arrived in 2023 by subleasing roughly 230,000 square feet at 500 Howard Street from Slack, which had gone remote-first and no longer needed a headquarters. That sublease has since been converted into a direct long-term lease with landlord Heitman at around 240,000 square feet.
From there the expansion was relentless. Roughly 100,000 square feet at 505 Howard. Then, in January, the entire 25-storey tower at 300 Howard Street — formerly 199 Fremont, a building that had sat empty and unloved through the city's post-pandemic office collapse — together with the adjacent low-rise at 342 Howard, for a combined figure reported at roughly 480,000 square feet on a thirteen-year term. Then three floors and 650 desks at 400 Howard. Then a short-term deal for about 70,000 square feet at 405 Howard, purely to house 350 people until the new headquarters is ready.
The 300 Howard transaction deserves particular attention from anyone who has spent the past four years reading obituaries for the American central business district. The tower had been acquired by DivcoWest and Blackstone for just over $111 million — the priciest San Francisco office deal of the post-pandemic years, which tells you how depressed the market was. It was fully vacant. One lease took it to one hundred percent occupancy.
No enterprise zone. No tax increment financing. No mayoral task force. A private buyer took a risk on a distressed asset, a private tenant needed space, and a price was agreed. This is what functioning capital markets look like when they are permitted to clear.
The New York expansion followed the same template at greater speed. Anthropic began the year shopping for between 250,000 and 450,000 square feet in Manhattan. It finished by taking the whole of AEW Capital Management's 465,630-square-foot building at 330 Hudson Street, exceeding even the top of its own stated range.
The prior Manhattan presence was 15,000 square feet at 155 Sixth Avenue — a lease that expires this year. The company has said it intends to double its New York headcount to 1,000 by year end, in a building sized for 1,700.
The macro picture is consistent. AI tenants have been absorbing Manhattan office space at roughly twice the previous year's pace, accounting for more than a third of technology-sector demand in a single quarter, according to JLL figures cited in the trade press. An industry that was supposed to make offices obsolete is the reason they are filling up again.
Anthropic has taken 158,000 square feet at One Triton Square in London's Knowledge Quarter, a building British Land recovered from Meta in 2023 after a £149 million lease surrender — another distressed asset absorbed by AI demand rather than public subsidy.
In Dublin, designated the company's EMEA headquarters, the office expanded sixfold to around 21,000 square feet alongside 200 new roles across engineering, sales, finance, legal and operations. Smaller offices operate in Paris, Zurich and Munich, with EMEA described in company communications as its fastest-growing region. Dublin's regulatory weight is not incidental: whoever holds the Irish entity carries meaningful responsibility under GDPR and, increasingly, under the EU AI Act.
There is a strategic argument buried in the property filings. The remote-work consensus of 2021 held that knowledge work could be distributed indefinitely without cost. Anthropic, a company whose entire product is distributed knowledge work, is voting with a thirteen-year lease that this is false — at least for frontier research, where the value of an unplanned corridor conversation is difficult to replicate over video.
It is also a bet on institutional density. Locating five buildings within a two-block radius is not an accident of availability. It is an attempt to preserve the physics of a small company inside a large one.
For all the noise the leasing spree generates, 1.6 million square feet of office is the small number. The data centre buildouts announced with Amazon and Google run to millions of square feet and tens of billions of dollars in committed capital. The desks house the people who design the models; the warehouses house the machines that run them, and it is the machines that consume the balance sheet.
Anyone assessing Anthropic's physical scale by counting offices is measuring the wrong thing by an order of magnitude.
A thirteen-year lease on an entire tower is a fixed obligation set against revenues that remain, by any historical standard, young. Anthropic raised $13 billion in September and has been spending against expectations rather than earnings. Should AI revenue growth disappoint, these commitments become the sort of legacy liability that has broken faster-growing companies than this one.
That is not a criticism. It is the nature of risk capital, and the willingness to bear it is precisely why San Francisco's Financial District is recovering while cities that waited for a public programme are still waiting. But the downside belongs to the people who signed the leases and the investors who funded them — not, this time, to the taxpayer. That distinction is worth defending.
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