Role and Responsibilities

The data space Governance Authority defines the requirements for participation and oversees the onboarding process of participants. Within this, the Participant Registry (PR) plays a facilitating role by operationalising these rules and supporting trust assurance. It acts as the practical mechanism through which governance decisions are executed.

The Participant Registry is responsible for managing the lifecycle and trust status of participants within a data space. Its responsibilities are laid out in the iSHARE Trust Framework and governed by the data space Governance Authority.

Onboarding and admission

A primary responsibility of the Participant Registry is to validate and onboard participants into a data space. This includes verifying that organisations meet the criteria defined by the governance authority and ensuring that onboarding processes are consistently applied.

The framework requires that the Participant Registry operates based on clearly defined processes and criteria for onboarding, registration, updating, and reviewing participants. These processes must align with the level of assurance for which the Participant Registry has been certified.

Note: To be onboarded to the iSHARE Ecosystem, either as an adhering or certified party, there is a specific admission criterion and onboarding process that the parties need to fulfil (See more here). This can be applied in Data Spaces where the iSHARE Trust Framework is integrated; however, each data space is free to further define criteria for its own participants.

Participant information management

The Participant Registry maintains information about all registered participants. This includes:

• identity and identifiers
• roles performed within the data space
• services offered
• level of assurance and compliance status

This information forms the basis for other participants to assess whether interaction is possible and under what conditions, in line with the access rules defined in the Authorisation Registry.

Claims management (Claim Models)

In line with the iSHARE Trust Framework version 3.0, participant information is structured around claims. The Participant Registry is responsible for registering and maintaining these claims, ensuring they are valid, up to date, and within the scope of the data space.

Claims represent specific attributes or statements about a participant, such as:

• membership in a data space
• roles performed
• certifications or credentials
• capabilities or services offered

The Participant Registry is responsible for maintaining these claims and ensuring they are:

• validated before registration
• aligned with governance rules
• traceable to their source

The framework also allows Participant Registries to maintain claims for participants registered by other registries, provided that governance and validation requirements are met. This supports interoperability across data spaces.

Membership and status validation (Maps to the Data Space Membership Claim)

The Participant Registry enables participants to verify whether another party:

• is a member of the data space (and currently active)
• meets the required compliance criteria (with the framework and data space)
• holds specific roles or attributes (level of assurance)

This validation is typically performed automatically by systems querying the Participant Registry before initiating interactions, and is fundamental for establishing trust before interactions take place.

Support for discovery

The Participant Registry builds the context of a data space and supports the discovery of relevant components within the iSHARE ecosystem.

Through endpoints such as /capabilities, participants can expose information about:

• available services
• supported functionalities
• relevant endpoints

This allows other participants to identify how and where to interact with a given party.

In addition, the Participant Registry plays a role in Authorisation Registry discovery, enabling service providers to determine the appropriate Authorisation Registry when it is not explicitly specified. For example, it must enable service providers to determine which Authorisation Registry to use when this information is not otherwise available.

Compliance and certification (maps to the Framework Compliance Claim)

As a certified role within the iSHARE Trust Framework, the Participant Registry must:

• comply with defined service levels for certified parties
• operate in accordance with its certified level of assurance
• avoid making claims beyond its certification scope

In addition, the Participant Registry itself must be registered as a participant, including its role, level of assurance, and compliance status.

What the Participant Registry does not do

To clarify its role within the architecture, the Participant Registry:

• does not enforce access control decisions (this is handled by Authorisation Registries)
• does not authenticate users or systems (this is the role of Identity Providers)
• does not directly participate in data exchange flows

Instead, it provides the trusted information layer that enables these processes to function reliably.