Anthropic is getting a fleet of data centres. Someone else is paying to build them

Anthropic, Macquarie Asset Management and Singapore’s GIC announced a partnership on Monday to develop data centres dedicated to Anthropic alone. The platform has a name, Theseus Infrastructure. It will develop, operate and lease the facilities to Anthropic under long-term contracts, and the partners will tailor each site to Anthropic’s compute needs.

The ownership line is the one to read twice. Macquarie Asset Management funds and GIC will jointly own Theseus and supply the majority of the equity for each project. Anthropic is the anchor tenant.

The release names no figures. No capital commitment, no gigawatts, no sites, no timeline. Bloomberg, which reported the venture, said the companies shared no details on planned spending or the size of the projects. The release quotes nobody either. Not one executive from any of the three parties appears in it.

Rent instead of capital

This is a financing structure before it is a building programme. A dedicated AI campus swallows equity for years before a single rack earns anything. Theseus hands that problem to investors who specialise in contracted infrastructure cash flows. Anthropic pays through rent rather than capital expenditure, and keeps the capacity.

The pattern is hardening across the sector. Meta shifted $279bn of data centre leases off its balance sheet. Google now guarantees $44bn of rent on buildings it will never own, and Anthropic already leases TPU capacity inside that arrangement. Bloomberg reports that Anthropic also took a $35bn loan to lease chips at five data centres, with Google standing behind it.

The timing sharpens the point. Anthropic is preparing a public listing. A company heading for public markets books rent as an operating expense and leaves construction risk with somebody else. In 2025 Anthropic said it would spend $50bn on custom US data centres, including sites in Texas and New York. Theseus points the other way.

The clause about your electricity bill

One sentence in the release carries more weight than the rest. Anthropic has committed to cover the electricity price increases that communities near these sites might otherwise face.

That echoes a pledge Anthropic published in February. It promised then to pay for 100% of the grid upgrades needed to connect its data centres, to bring net-new generation online to match their demand, to curtail power use at peak, and to cool with less water.

The document also carried a caveat. Where Anthropic leases capacity from existing data centres, it said only that it was “exploring further ways to address our own workloads’ effects on prices.”

Theseus sits between the two categories. The sites are leases, but purpose-built ones. On Monday’s wording, the stronger commitment now travels with them.

What the release does not name is an auditor. No third party verifies the calculation, no regulator signs it off, and the promise covers price rises from these sites rather than the aggregate strain a build-out puts on a grid. Seven companies signed the White House Ratepayer Protection Pledge in March, and those commitments stayed voluntary too. Anthropic was not among the seven.

The seller becomes the builder

Macquarie’s side of this has an odd rhythm. It owned Aligned Data Centers from 2018 and grew it from two facilities and 85MW into a hyperscale operator. Then it closed the $40bn sale to the AI Infrastructure Partnership, MGX and BlackRock’s Global Infrastructure Partners on 20 July. Three weeks later it announced a new platform. Macquarie Asset Management managed $497.6bn as at 31 March.

GIC raises a separate question. It invests Singapore’s foreign reserves, employs more than 2,500 people across 11 financial centres and holds assets in over 40 countries. Sovereign capital now underwrites American AI compute, and that argument has not run its course.

Anthropic itself accepts that action by one company is not enough. Everything else about Theseus remains unquantified: the money, the megawatts, the locations, and the “thousands” of construction and permanent jobs. The first useful test is where the first site lands, and what the local utility says when it gets there.