Summary The proposed Cloud and AI Development Act (CADA) creates two distinct catalogues serving different strategic purposes. Article 4(2)(e) mandates the establishment of a "catalogue of European open cloud computing solutions" as part of the Cloud and AI Leadership Initiatives. This catalogue would showcase end-to-end cloud stacks (hardware and software) developed under operational objective 2 to strengthen technological autonomy. Crucially, this is not the same as the EU Open Source Solutions Catalogue established under Article 43, which is a separate mechanism for public sector bodies to share and reuse general software. The Article 4 catalogue focuses on industrial infrastructure and supply-chain resilience, while the Article 43 catalogue focuses on administrative efficiency and software reuse.

Detail

The Cloud and AI Development Act (CADA), as proposed in COM(2026) 502 final, structures its strategy for technological sovereignty through the "Cloud and AI Leadership Initiatives." These initiatives are designed to bridge the gap between research and large-scale deployment. A key component of this framework is the creation of specific catalogues to make European solutions visible and accessible.

The Article 4(2)(e) Catalogue: Industrial Cloud Stacks

The specific mandate for the catalogue of European open cloud computing solutions is found in Article 4(2)(e) of the proposal. This provision falls under operational objective 2, which is dedicated to "supporting the development and deployment of cloud computing stacks supporting the Union's technological autonomy."

The text of Article 4(2)(e) states that the Cloud and AI Leadership Initiatives shall:

"establish a catalogue of European open cloud computing solutions developed under points (a) to (d) of this paragraph."

To understand the scope of this catalogue, one must examine the preceding points of Article 4(2), which define the specific technologies and stacks to be developed:

  • Article 4(2)(a): Focuses on "secure, resilient and performant open cloud computing stacks." These are comprehensive solutions covering "on-device edge, connectivity, data and AI tools, backend and service layers for strategic sectors."
  • Article 4(2)(b): Targets "AI-optimised servers and baseline software based on processors, accelerators and quantum accelerators designed and manufactured in the Union."
  • Article 4(2)(c): Aims to boost data availability via "open-source middleware platforms underpinning common European data spaces."
  • Article 4(2)(d): Supports the creation of "open-source software foundations supporting open-source components."

Consequently, the catalogue under Article 4(2)(e) would not be a simple list of generic applications. It would be a curated repository of integrated infrastructure solutions. It would feature:

  1. Full Stacks: End-to-end architectures combining hardware (servers, accelerators) and software (middleware, AI tools).
  2. Strategic Focus: Solutions specifically designed for strategic sectors (e.g., healthcare, energy, defence) as outlined in the "Grand Challenges" in Annex I (specifically Grand Challenge 2: Cloud stacks).
  3. Sovereignty Alignment: Solutions developed to reduce dependencies on non-European providers and enhance the EU's industrial base.

This catalogue serves as a market signal, highlighting European alternatives that meet the specific criteria of operational objective 2. It is an instrument of industrial policy, intended to foster a competitive ecosystem of European cloud providers and technology developers.

Distinction from the Article 43 EU Open Source Solutions Catalogue

A frequent point of confusion arises from the existence of a second catalogue: the EU Open Source Solutions Catalogue (EU OSS Catalogue) established under Article 43. While both catalogues promote open technology, they are legally distinct, serve different objectives, and target different user bases.

1. Legal Basis and Objective

  • Article 4(2)(e) Catalogue:
    • Basis: Part of the Cloud and AI Leadership Initiatives (Title II).
    • Objective: To strengthen technological autonomy and industrial competitiveness. It aims to showcase solutions that build the EU's cloud infrastructure capacity and reduce supply-chain dependencies.
    • Target: Developers, industrial partners, and public buyers looking for sovereign infrastructure stacks.
  • Article 43 EU OSS Catalogue:
    • Basis: Part of the Open Source chapter (Title IV, Chapter V).
    • Objective: To facilitate the sharing and reuse of software by public administrations to reduce duplication and maximize public expenditure value.
    • Target: Union entities and public sector bodies looking for reusable software components (e.g., administrative tools, specific applications).

2. Scope of Content

  • Article 4(2)(e): Contains cloud computing solutions and stacks. This includes complex, integrated systems involving hardware-software co-design, middleware for data spaces, and AI-optimised server software. It is tied to the "Grand Challenges" of building capacity.
  • Article 43: Contains software made available for reuse under an open-source licence. As per Article 42, when a Union entity or public sector body makes software available for reuse, it must do so via a repository connected to this catalogue. The scope is broader and less specific to cloud infrastructure stacks; it covers any public-sector software.

3. Mechanism of Creation

  • Article 4(2)(e): Solutions are included because they are developed under the specific operational objectives of the Cloud and AI Leadership Initiatives. The catalogue is a result of R&D and deployment funding and strategic direction.
  • Article 43: Solutions are included because a public body voluntarily decides to make them available for reuse. The catalogue acts as a centralised discovery point for existing public-sector software assets.

Why the Distinction Matters

The separation reflects the CADA proposal's dual approach:

  1. Supply-Side (Article 4): Building the infrastructure (cloud stacks, servers, middleware) to ensure the EU has the capacity and autonomy to run its digital economy.
  2. Demand-Side (Article 43): Optimising the use of software by public bodies to avoid reinventing the wheel and to foster a culture of reuse.

Confusing the two could lead to strategic errors. A public body seeking a sovereign cloud infrastructure provider should look to the Article 4(2)(e) catalogue for stack-level solutions. A public body seeking a reusable citizen portal or internal HR tool should look to the Article 43 catalogue.

What this means for you

For technology leaders, developers, and public procurement officers, understanding the bifurcation of these catalogues is essential for navigating the CADA landscape.

For Cloud Providers and Technology SMEs

If your company is developing open-source cloud stacks, middleware, or AI-optimised hardware/software, Article 4(2)(e) is your primary target.

  • Strategic Alignment: Align your R&D with operational objective 2. Solutions that fit the definition of "secure, resilient and performant open cloud computing stacks" are the ones that would be featured in this catalogue.
  • Visibility: Inclusion in this catalogue would signal that your solution contributes to the EU's strategic autonomy, potentially making it a preferred choice for public procurement under Article 32 (Union added value criteria).
  • Differentiation: Do not confuse this with general open-source repositories. The value proposition here is sovereignty and stack integration, not just code availability.

For Public Sector Bodies and CTOs

You will likely interact with both catalogues, but for different reasons.

  • Infrastructure Procurement: When procuring cloud services or building new digital infrastructure, consult the Article 4(2)(e) catalogue (once established) to identify European open cloud stacks that meet sovereignty requirements. This is critical for activities identified as contributing to public order under Article 29.
  • Software Reuse: When developing or acquiring specific software applications (e.g., tax portals, health records systems), check the Article 43 EU OSS Catalogue first. Article 42 encourages public bodies to reuse existing software rather than developing new code, reducing costs and fragmentation.
  • Compliance: Ensure your procurement strategies distinguish between "cloud stack" requirements (infrastructure sovereignty) and "software reuse" requirements (administrative efficiency).

For Investors and Analysts

The Article 4(2)(e) catalogue represents a significant market signal. It indicates where the EU intends to direct funding and policy support to build a competitive cloud industry. Startups and SMEs developing components for these stacks (e.g., quantum accelerators, open middleware) are likely to see increased demand and potential public-sector partnerships.

Common misconceptions

"The CADA proposal creates a single 'Open Source Catalogue' for everything." Incorrect. The proposal explicitly creates two separate mechanisms. Article 4(2)(e) creates a catalogue for cloud computing solutions developed under leadership initiatives (infrastructure focus). Article 43 creates the EU Open Source Solutions Catalogue for software reuse by public bodies (administrative focus). They are governed by different articles and serve different policy goals.

"The Article 4 catalogue is just a list of all open-source software in Europe." No. The Article 4(2)(e) catalogue is restricted to solutions "developed under points (a) to (d)" of Article 4(2). This limits it to specific cloud stacks, AI-optimised servers, middleware for data spaces, and open-source foundations that are part of the Cloud and AI Leadership Initiatives. It is a curated list of strategic infrastructure, not a general directory.

"Public bodies must use the Article 4 catalogue for all software procurement." No. The Article 4 catalogue is relevant for cloud computing services and infrastructure stacks, particularly where sovereignty and public order are concerns. For general software applications, the Article 43 catalogue is the relevant tool for identifying reusable solutions. Procurement rules under Article 30 and Article 32 will dictate which catalogue is relevant based on the subject matter of the contract.

Related

This is general information about a draft EU regulation, not legal advice.