Web 4.0 architectural framework and Open Internet Stack applications for virtual worlds (RIA)

The HORIZON-CL4-2026-04-HUMAN-02 grant opportunity aims to develop Web 4.0 and virtual world solutions under the Horizon Europe program. This action is categorized as a Research and Innovation Action (RIA), focusing on both an architectural framework and open internet stack applications. The total funding available is €16.8 million, with three projects expected to be funded, providing individual grants ranging from €2.8 million to €8.4 million.

Eligible applicants include a diverse set of legal entities such as universities, research institutions, small and medium-sized enterprises (SMEs), large enterprises, public institutions, and non-profit organizations. Collaboration is encouraged in project proposals, although a consortium is not strictly required. The call primarily targets entities within the European Union and Associated Countries, specifically excluding legal entities established in China.

The funding mechanism is a grant structure that allows for direct financial support to successful applicants, with the option to distribute part of the budget as financial support to third-party contributors, particularly within European open-source communities. The project stage is expected to involve applied research and early-stage innovation activities, focusing on developing scalable and mature technological solutions.

The call's thematic focus emphasizes digital technology sectors, particularly next-generation internet technologies that enhance interoperability, security, and user trust. Successful projects should demonstrate the technical maturity necessary for real-world application and alignment with EU values of privacy, security, and compliance.

The application process follows a single-stage submission method, with proposals due by April 15, 2026. The evaluation for funding includes administrative checks and an assessment against defined award criteria.

Overall, this opportunity reflects the European Commission's commitment to fostering innovation in digital technology, promoting technological sovereignty, and enhancing global competitiveness through the advancement of open-source solutions and frameworks toward a more decentralized and trustworthy internet infrastructure.

This EU funding opportunity, HORIZON-CL4-2026-04-HUMAN-02, aims to stimulate the emergence of Web 4.0 and virtual world solutions at a European and global scale. It falls under the Horizon Europe program, specifically the DIGITAL (HORIZON-CL4-2026-04) call, and is a HORIZON Research and Innovation Action (HORIZON-RIA). The projects funded under this topic are expected to contribute to an emerging Web 4.0 architectural framework composed of cross-platforms, interoperable, trustable, safe, and secure building blocks that rely on Open Source software. It also aims to create a structured and agile ecosystem of talented contributors driving the creation and evolution of commons based on Open Source software, open standards, and open hardware and designs. Furthermore, the projects should lead to open-source, European-made solutions that support trust and sovereignty, offering credible alternatives for citizens, governments, and companies, including start-ups and SMEs. These solutions should be interoperable, standards-based, decentralized, and exploit extended reality technologies, while also being compliant with EU rules and regulations and easily deployable by European providers, integrators, and verticals.

The scope of the funding opportunity is divided into two main areas:

1. Architectural Framework: This area focuses on developing a human-centric Web 4.0 architectural framework. This framework should encompass interoperable layers from open hardware, the web, AI agents, and immersive and decentralized applications. It should utilize cross-platform digital commons developed by European innovators, including SMEs, start-ups, and academia. Proposals should demonstrate immersive multi-modal user interaction and enhance trust, privacy, portability, and advanced identity management. The framework should also facilitate the deployment of the EU Wallet while optimizing the balance between decentralization, security, and energy efficiency with verifiable metrics.

2. Applications: This area focuses on developing specific technologies for Web 4.0 and virtual worlds. These technologies include:

Alternative decentralized applications and services, such as synchronous and asynchronous messaging, videoconferencing, collaboration and groupware, or social media, that can be exploited through Virtual Worlds technologies, including immersion and interaction.

App-stores (including web-based) adapted for Virtual Worlds.

Shared, robust, and trustworthy cross-technology Virtual Worlds for user and attribute management.

Proposals in this area must demonstrate technical maturity in terms of scalability, resiliency, and alignment with standards. They must also show a critical mass of communities actively supporting the development and evidence of interest from users and deployers of the solutions.

There are also cross-cutting requirements that apply to both areas. Applicants must define mechanisms for maturing building blocks, such as security and accessibility audits, packaging of the software for easy deployment, localization of the software in EU languages, documentation of best practices, and advising on licensing. They should also detail the path to growth for building blocks, including defining a clear standardization strategy, actively animating communities, creating momentum among like-minded efforts, defining how projects will gain critical mass, and providing a coherent picture of the portfolio for adopters. Applicants should create conditions for successful collaboration and synergies with other European initiatives, such as the Virtual Worlds/Web 4.0, 3C, and Open Internet Stack initiatives, as well as with like-minded funding efforts at national, European, and international levels. Applicants should demonstrate their experience and understanding of Open Source communities and their expertise covering the full Open Source life cycle through a proven track record.

Beneficiaries who intend to transfer ownership or grant an exclusive license must formally notify the granting authority (DG-CNECT and HaDEA) before the intended transfer or licensing takes place. The granting authority may object to a transfer of ownership or the exclusive licensing of results up to four years after the end of the action.

Financial support to third parties is allowed, and applicants should target calls towards European Open Source communities, including SMEs, research institutes, and individual researchers and developers with solid experience in developing solutions in line with EU rules and values. Applicants should provide the program logic for the third-party projects, manage the projects lifecycle, and provide the necessary technical and non-technical support.

The funding opportunity is part of the broader effort to drive human-centric innovation through digital and industrial technologies. It aims to strengthen Europe’s capacity to innovate, deploy, and scale trustworthy virtual worlds, thereby strengthening competitiveness, resilience, and alignment with EU values. The development of a robust Web 4.0 architectural framework, underpinned by open-source solutions and shared standards, is seen as essential to ensure interoperability, decentralization, and trust.

Legal entities established in China are not eligible to participate in both Research and Innovation Actions (RIAs) and Innovation Actions (IAs) falling under this destination.

The general conditions for participation include admissibility conditions related to proposal page limits and layout, eligible countries, and other eligibility criteria. Applicants must also demonstrate financial and operational capacity and must not be subject to exclusion criteria. The evaluation and award process will consider award criteria, scoring, and thresholds, as well as submission and evaluation processes and an indicative timeline for evaluation and grant agreement. The legal and financial setup of the grants will follow the standard Horizon Europe rules.

The budget for the HORIZON-CL4-2026-04-HUMAN-02 topic is 16,800,000 EUR, with contributions ranging from 2,800,000 to 8,400,000 EUR and an indicative number of 3 grants. The planned opening date for submissions is 15 January 2026, and the deadline for submissions is 15 April 2026 at 17:00:00 Brussels time.

Additional information and guidance are available through the Horizon Europe Programme Guide, Model Grant Agreements, call-specific instructions, and various support services, including National Contact Points, the Enterprise Europe Network, and IT Helpdesks.

In summary, this funding opportunity seeks to foster the development of a human-centric and trustworthy Web 4.0 and virtual world ecosystem in Europe, based on open-source principles, interoperable standards, and collaboration among European innovators. It is divided into two main areas: architectural framework development and application development, with specific requirements and funding allocations for each. The ultimate goal is to strengthen Europe’s digital sovereignty, competitiveness, and alignment with its core values in the evolving landscape of the internet and virtual worlds.

Eligible Applicant Types: The eligible applicant types for this opportunity include SMEs, start-ups, academia, research institutes, and individual researchers and developers. The call specifically targets European innovators and Open Source communities.

Funding Type: The primary financial mechanism is a grant. Financial support to third parties is also provided in the form of grants.

Consortium Requirement: While not explicitly stated, the nature of the projects, particularly the "Architectural Framework" area, suggests that a consortium of multiple applicants is highly encouraged, if not required, to bring together the necessary expertise and resources. The "Applications" area may be suitable for single applicants, but collaboration is still beneficial.

Beneficiary Scope (Geographic Eligibility): The geographic eligibility primarily focuses on European entities, including EU Member States and associated countries. The call also mentions synergies with like-minded funding efforts beyond Europe, suggesting some international collaboration may be possible, but the core beneficiaries should be European. Legal entities established in China are explicitly ineligible. A number of non-EU/non-Associated Countries that are not automatically eligible for funding have made specific provisions for making funding available for their participants in Horizon Europe projects.

Target Sector: The program targets the digital sector, specifically focusing on Web 4.0, virtual worlds, open internet stack, AI agents, open hardware, decentralized applications, digital commons, and extended reality technologies. It also touches upon areas like trust, privacy, identity management, security, and energy efficiency within the digital space.

Mentioned Countries: China is explicitly mentioned as ineligible. The primary geographic focus is Europe, including EU Member States and associated countries. There is also a mention of collaboration with like-minded funding efforts beyond Europe.

Project Stage: The expected maturity of the project varies depending on the area. The "Architectural Framework" area seems to target projects in the research, development, and demonstration stages, aiming to create an emerging framework. The "Applications" area targets projects with technical maturity, scalability, and evidence of user interest, suggesting a focus on validation, demonstration, and potentially commercialization.

Funding Amount: The funding amounts vary depending on the specific topic within the call. The budget overview provides the following ranges:
HORIZON-CL4-2026-04-DATA-02: EUR 7,000,000 to EUR 10,250,000
HORIZON-CL4-2026-04-DATA-03: Around EUR 4,000,000
HORIZON-CL4-2026-04-DATA-06: EUR 11,500,000 to EUR 23,500,000
HORIZON-CL4-2026-04-DIGITAL-EMERGING-01: Around EUR 17,000,000
HORIZON-CL4-2026-04-DIGITAL-EMERGING-08: Around EUR 18,000,000
HORIZON-CL4-2026-04-DIGITAL-EMERGING-09: Around EUR 6,000,000
HORIZON-CL4-2026-04-DIGITAL-EMERGING-11: Around EUR 500,000
HORIZON-CL4-2026-04-DIGITAL-EMERGING-12: Around EUR 1,000,000
HORIZON-CL4-2026-04-DIGITAL-EMERGING-14: Around EUR 3,000,000
HORIZON-CL4-2026-04-DIGITAL-EMERGING-15: Around EUR 1,000,000
HORIZON-CL4-2026-04-DIGITAL-EMERGING-17: Around EUR 1,000,000
HORIZON-CL4-2026-04-DIGITAL-EMERGING-18: Around EUR 10,000,000
HORIZON-CL4-2026-04-DIGITAL-EMERGING-19: Around EUR 15,000,000
HORIZON-CL4-2026-04-HUMAN-01: EUR 4,000,000 to EUR 5,000,000
HORIZON-CL4-2026-04-HUMAN-02: EUR 2,800,000 to EUR 8,400,000

Application Type: The application type is an open call with a single-stage submission process.

Nature of Support: Beneficiaries will receive money in the form of grants. The opportunity also emphasizes non-monetary services such as security and accessibility audits, software packaging, localization, documentation, and best practices advising.

Application Stages: The application process is a single-stage process.

Success Rates: The success rates are not explicitly mentioned. However, the indicative number of grants for each topic provides some insight into the potential success rate, which will likely vary depending on the number of applications received.

Co-funding Requirement: The information does not explicitly state a co-funding requirement. As this is a Horizon Europe action, co-funding is possible but not specifically mentioned in the text.

Summary: This Horizon Europe call, under the DIGITAL program, aims to stimulate the emergence of Web 4.0 and virtual world solutions by funding research and innovation actions. It focuses on two main areas: developing a human-centric Web 4.0 architectural framework and supporting open internet stack applications for virtual worlds. The call encourages European innovators, including SMEs, start-ups, and academia, to develop cross-platform, interoperable, and trustworthy building blocks based on open-source software and hardware. The funding supports projects from research and development to validation and demonstration, with a strong emphasis on creating synergies with other European initiatives and fostering collaboration within Open Source communities. The call provides financial support through grants, with specific budget allocations for different topics, and encourages financial support to third parties, particularly European Open Source communities. The ultimate goal is to strengthen Europe's competitiveness and technological sovereignty in the digital realm by driving investment in advanced hardware, immersive interaction, and seamless integration across the Telco-Cloud-to-Edge continuum. Legal entities established in China are not eligible to participate.