Summary
- CoreWeave contributed 8.6% of Merlin's group rental income in the first half of 2026.
- The customer represents approximately 80% of the group's 160MW of currently leased or pre-let data centre capacity.
- Merlin plans to expand its platform to 724MW across three development phases and reduce individual tenant concentration.
Merlin Properties has clarified its exposure to CoreWeave, stating that the US AI infrastructure provider contributed 8.6% of group rental income in the first half of 2026 while accounting for approximately 80% of its currently leased or pre-let data centre capacity.
The Spanish property group provided the figures to analysts as concerns about CoreWeave’s financing and debt obligations increased scrutiny of companies exposed to its infrastructure expansion.
Merlin’s data centre business has 160MW of capacity leased or pre-let, including agreements for facilities that have not yet entered commercial operation. The company’s first three development phases encompass a planned 724MW of IT capacity.
Those figures describe different stages of development. Leased or pre-let capacity is backed by customer agreements, but it cannot all be treated as completed, connected, or generating the full revenue anticipated under those contracts.
CoreWeave’s concentration within the existing leased portfolio is consequently much greater than its contribution to rental income across Merlin’s diversified property business.
Merlin owns offices, shopping centres, and logistics properties alongside its expanding data centre platform. Income from those established assets means that the company’s overall financial exposure cannot be measured solely by the proportion of its data centre capacity associated with CoreWeave.
The clarification follows growing attention to the financing of AI infrastructure providers and the obligations associated with their extensive computing and data centre commitments.
Existing leases and future capacity
Merlin’s MEGA development programme is divided into three phases, with a total planned capacity of 724MW IT across the initial programme.
The first phase encompasses 64MW IT and is fully let and equipped. The company’s July results identified operational rental income at Barcelona and Bilbao-Arasur, while Madrid-Getafe remained dependent on electricity connections expected during the fourth quarter of 2026.
Its second phase comprises 254MW IT, with development activity extending across Spain and Portugal. Merlin has reported additional leases signed well before the planned delivery dates of individual facilities.
The third phase adds a proposed 406MW IT, including further development at Bilbao-Arasur, Lisbon, and Zaragoza. Several components remain in construction planning or earlier development stages.
The distinction between those phases is central to the company’s future concentration risk. Merlin expects additional tenants to join the platform as further buildings are developed and leased, reducing the proportion attributable to any single customer.
Analyst reporting indicates that Merlin intends to bring individual customer exposure below 20% once its data centre development programme is substantially completed.
That remains a commercial objective rather than an achieved position. Diversification will require new lease agreements, completed facilities, and customer demand sufficient to occupy additional capacity.
Even a signed lease does not eliminate the physical constraints associated with delivery. Buildings require electricity connections, distribution systems, cooling equipment, network infrastructure, and the commissioning work needed before occupiers can use the contracted capacity.
The development timetable therefore influences when additional leases begin generating their expected income and how quickly the company’s customer concentration can decline.
Contractual protections have practical limits
Merlin says its data centre leases include contractual guarantees and other protections intended to reduce its exposure to tenant payment difficulties.
The company has also referred to provisions that could allow it to interrupt electricity supply in the event of non-payment and pursue remedies under the relevant agreements.
These are protections described by Merlin and its analysts. Their effectiveness in any particular dispute would depend on the contractual wording, applicable law, and circumstances involved. No finding has established that CoreWeave has failed to meet its rental obligations to Merlin.
Although the reported protections may strengthen the landlord’s position, a specialist data centre cannot necessarily be reassigned to another customer as readily as conventional commercial property.
Electrical capacity, cooling specifications, equipment ownership, network connections, and the configuration of individual data halls influence the work required to accommodate a replacement tenant.
Some facilities can support different occupiers with limited modification, while others may have been developed around requirements specific to a particular computing provider.
A transition can also be complicated by the distinction between infrastructure owned by the landlord and computing equipment installed by its customer.
Consequently, the commercial value of contractual protections cannot be assessed independently of the underlying property’s technical condition and the availability of other potential occupiers.
Concerns surrounding CoreWeave arise partly from the substantial borrowing used to finance its expansion. Financing costs and the delivery of future computing contracts can affect the financial outlook of a tenant without necessarily creating an immediate default under its property leases.
Merlin’s established rental portfolio provides diversification at group level, while the planned data centre expansion offers an opportunity to reduce concentration within the newer division.
Neither factor removes the need to monitor the tenant’s financial performance and the completion of facilities already committed under long-term agreements.
The next meaningful indicators will be the delivery of additional leased capacity, the timing of electricity connections, and the proportion of the data centre portfolio contracted to customers other than CoreWeave.
