The European Commission is poised to designate Microsoft Azure and Amazon Web Services as “gatekeeper” cloud platforms under the Digital Markets Act, with preliminary findings expected as early as this week. The move, if confirmed, would mark a dramatic expansion of the EU’s landmark antitrust tool into the hyperscale cloud computing market, subjecting two of the world’s largest technology providers to a strict set of behavioral obligations and opening a new front in Brussels’ decade-long effort to rein in Big Tech.

The looming decision follows months of investigation into whether cloud infrastructure services constitute a core platform service under the DMA. While the regulation has already designated gatekeepers in social media, search, online advertising, and mobile ecosystems—including Alphabet, Amazon (for its marketplace and advertising), Apple, ByteDance, Meta, and Microsoft (for Windows PC operating system and LinkedIn)—cloud computing has so far remained outside its scope. That is about to change, and for Microsoft, the consequences could ripple far beyond Azure billings into the very architecture of its Windows ecosystem.

The DMA’s Gatekeeper Criteria and Why Cloud Now Qualifies

Under the DMA, a company is considered a gatekeeper if it has significant economic power, serves as an important gateway between businesses and consumers, and holds an entrenched market position. Quantitative thresholds include annual EU revenue of at least €7.5 billion in each of the past three years, a market capitalization of at least €75 billion, and the operation of a core platform service with more than 45 million monthly active end users and over 10,000 yearly business users in the EU.

Cloud computing was not originally listed among the core platform services, but the DMA empowers the Commission to add new categories through a market investigation. After receiving complaints from European cloud providers and industry groups, the EU executive launched a probe into cloud infrastructure services in late 2023. Early indicators suggest that both AWS and Azure easily surpass the user and revenue thresholds. AWS commands roughly 32% of global cloud infrastructure spending, with Microsoft Azure at 23% and growing fast on the back of AI and enterprise software bundling. In Europe, their dominance is even more pronounced, leaving little doubt that they function as essential gateways for businesses migrating to the cloud.

What the Preliminary Findings Will Say

The preliminary findings, expected to be communicated to both companies confidentially, will likely assert that AWS and Azure meet the criteria for gatekeeper designation in the cloud infrastructure services market. This would trigger a mandatory compliance period of six months, during which the companies must implement a suite of far-reaching obligations. The final designation decision, which could come by mid-year, would then open the door to fines of up to 10% of global annual turnover for non-compliance.

Crucially, the probe is not just a tick-box exercise. It stems from persistent allegations of anti-competitive behavior, such as tying Azure to Microsoft’s own productivity software, imposing prohibitive egress fees that lock customers in, and creating technical barriers to interoperability. The DMA’s obligations are designed to dismantle precisely these types of gatekeeper advantage.

How This Hits Microsoft Hardest

While both AWS and Azure face scrutiny, the implications for Microsoft are particularly profound because of the company’s unique position across multiple DMA-regulated silos. Microsoft’s Windows operating system was already designated a gatekeeper service in 2023, meaning the company must allow rival app stores on Windows and give users the ability to uninstall pre-loaded apps. LinkedIn, too, fell under the DMA’s social network provisions. Adding Azure to this list would mean that a significant chunk of Microsoft’s enterprise revenue—cloud infrastructure and platform services—now faces the same intrusive regulatory oversight.

For the tens of millions of Windows users in the EU, the ripple effects could be immediate. The DMA could force Microsoft to unbundle Azure from its ever-tighter integration with Windows 11 and Microsoft 365. Currently, a Windows device steers users toward OneDrive for cloud storage, Teams for communication, and Azure Active Directory for identity management. Under new interoperability obligations, Microsoft might be required to let users easily choose rival cloud storage, identity providers, and collaboration tools from third-party clouds like Google or smaller European providers. The tight coupling that has made Microsoft’s ecosystem sticky would loosen, potentially eroding the convenience factor that keeps many enterprises locked in.

The Death of Egress Fees and Unfair Licensing

One of the most concrete changes would be an outright ban on egress fees—the charges levied when a customer moves data out of a cloud. Both AWS and Azure impose data transfer fees, which critics say serve only to trap customers and stifle multi-cloud strategies. The DMA would prohibit such charges, effectively making it free to leave. Microsoft recently abolished egress fees for its European customers after a 2024 settlement with the Cloud Infrastructure Services Providers in Europe (CISPE), but that agreement applied only to Azure and came with exceptions. A DMA mandate would be far broader and permanent, covering not just storage exit but also application migration.

Licensing is another flashpoint. For years, independent software vendors have complained that Microsoft charges more to run its server software—Windows Server, SQL Server—on rivals’ clouds than on Azure. This “Bring Your Own License” price discrimination is exactly the kind of self-preferencing the DMA wants to stamp out. If Azure is designated a gatekeeper, Microsoft would be forced to offer equivalent licensing terms for competing clouds, stripping away the artificial cost advantage that funnels so many workloads to Azure.

The Interoperability Mandate

A core DMA requirement is that gatekeepers must provide third-party platforms with the same interoperability structures they use internally. For Azure, that could mean opening up APIs and management interfaces so that rival cloud providers can offer seamless hybrid-cloud experiences. Currently, Microsoft’s hybrid tools like Azure Arc are optimized for Azure, making it easier to manage on-premises Windows servers with Azure services than with third-party infrastructure. Under the new rules, competitors could demand equal access to those management layers, possibly through standardised interfaces. The result could be a more level playing field, where a European cloud like OVHcloud or Deutsche Telekom can offer the same deep integration with on-premises Microsoft software as Azure does.

Industry Reaction and the CISPE Precedent

The industry’s response has been split between cautious optimism and deep skepticism. European cloud providers, long vocal about the unfair advantage hyperscalers enjoy, welcome the probe as a validation of their complaints. “This is exactly the kind of gatekeeper power the DMA was designed to curb,” said a representative from a French cloud lobby, while noting that final designation is only the first step; enforcement will be the real test.

On the other hand, American tech giants have lobbied heavily against the designation. In a previous response to the DMA’s original gatekeeper designations, Microsoft argued that the obligations could undermine cybersecurity and innovation. For cloud, both Microsoft and AWS are likely to push back on any requirement that forces them to reveal proprietary architectures or weaken security boundaries. They may warn that unfettered interoperability could create new attack vectors, a sensitive point given recent high-profile cloud breaches.

The recent CISPE settlement complicates the picture. In 2024, Microsoft agreed to pay a multi-million euro settlement and revamp its licensing practices to resolve a CISPE antitrust complaint—without a formal DMA finding. That agreement was seen by some as a strategic move to head off tougher regulation. However, the Commission appears unconvinced that voluntary changes go far enough, and the probe has continued. Now, with a gatekeeper designation looming, the tentative peace deal could be superseded by legally binding mandates that go well beyond what Microsoft offered in the settlement.

For Windows Users: More Choice, Possible Disruption

For the average Windows user in Europe, the short-term impact might be a flurry of new pop-up choice screens and configuration options—much like the browser ballot screen that appeared in Windows two decades ago. Upon setting up a new Windows PC, users might be asked which default cloud storage they prefer, which identity provider to use, or which communication platform to connect. Enterprise IT administrators would gain the ability to more easily mix and match services, potentially lowering costs and improving resilience.

However, interoperability requirements could also introduce software complexity and compatibility issues. When Windows 11 was built around deep cloud integration, adding alternative services requires rigorous testing that might not happen overnight. Users could encounter glitches if Microsoft’s apps are forced to work with third‑party clouds that don’t offer the same underlying infrastructure. Microsoft has warned that some DMA requests could “degrade the security and privacy” of its services. While that argument may be self-serving, it’s not entirely without merit: opening up closed systems always entails risk.

A Wider Regulatory Storm

The EU’s cloud probe unfolds against a backdrop of global antitrust action. The UK’s Competition and Markets Authority is also investigating cloud services, with a focus on egress fees and licensing. In the US, the Federal Trade Commission is examining cloud market concentration, though action remains uncertain under a business-friendly administration. The EU is positioning itself as the world’s de facto tech regulator, and a gatekeeper designation for cloud would further cement that role.

For Microsoft, the designation would sharpen a déjà vu of its bruising antitrust battles of the 2000s, when it was forced to unbundle Internet Explorer from Windows and open its APIs to third-party software. The parallels are stark: then, the issue was the operating system; now, it’s the cloud that is becoming the platform on which everything runs. Microsoft’s response then—grudging compliance paired with slow, incremental change—could be a playbook for what comes next.

What Comes Next

After the preliminary findings, both companies will have an opportunity to respond and argue their case before a final designation is issued. That final decision could come by late summer or early autumn 2025. From that point, they have six months to comply or face investigation for non-compliance. Given the complexity of cloud services, expect a drawn-out process of proposals, counter-proposals, and technical standardization debates.

In the interim, Microsoft is unlikely to wait idly. The company has already begun restructuring some of its software bundles and licensing agreements in Europe, trying to preempt the DMA’s demands. But if the Commission includes cloud infrastructure in its gatekeeper regime, Microsoft will be forced to make concessions that fundamentally alter how it sells and integrates its most profitable enterprise products. For Europe’s businesses and Windows users, the coming months promise more choice, more complexity, and a front-row seat to one of the most consequential tech regulation fights in a generation.