Verifiable Credentials: The Digital Passport for Businesses in Data Spaces

Every time a company starts working with a new supplier or client, the same familiar ritual repeats itself: exchanging PDF certificates, emails requesting confirmation of tax details, phone calls to verify that a document hasn't expired. It's a slow, manual process that also has to be repeated with every new business partner, because each certificate only proves something at a very specific moment and in a very specific context. Verifiable credentials exist precisely to break that cycle.

In a data space, where two organizations that haven't previously known each other may need to exchange sensitive information, this problem is compounded: before sharing a single piece of data, a basic question needs answering — who is the organization really on the other side of the connector, and can I trust that it is who it claims to be? Solving that question with manual processes doesn't scale.

In this article, we explain what verifiable credentials and decentralized identifiers (DIDs) are, how they work without relying on an intermediary for every verification, and why they're becoming the go-to trust mechanism for B2B onboarding in data spaces.

What Verifiable Credentials Are

A verifiable credential is a digital document, defined by a W3C standard, that certifies a claim about an entity — for example, that a company is registered in a commercial registry, holds a specific quality certification, or is part of a given data space. Unlike a signed PDF, a verifiable credential is built so that its authenticity can be checked automatically and cryptographically, without having to call the issuer to confirm it's still valid.

Every verifiable credential involves three actors:

• The issuer, the entity that issues the credential (a professional association, an administration, a certifying body, or the data space operator itself).
• The holder, the organization or person to whom the credential is issued and who stores it in their own digital repository.
• The verifier, the entity that, at the moment of a transaction, checks the presented credential without needing to contact the issuer directly.

This separation of roles is what allows a company to present its credentials as many times as needed, to different verifiers, without each verification depending on a real-time query to the issuing body.

Decentralized Identifiers: The Foundation of Corporate Digital Identity

Verifiable credentials rely on decentralized identifiers, known as DIDs. A DID is a unique identifier, generated and controlled by the organization itself, that doesn't depend on a centralized registry managed by a third party to exist or to prove ownership.

The W3C standard that defines DIDs doesn't impose a single method: several recognized ones exist, and real-world data spaces usually combine more than one. The two most common approaches in B2B environments are complementary: did:web, which publishes the identifier under the organization's own domain, requires no additional infrastructure, and is very simple to adopt and verify; and methods anchored on a distributed ledger network, which register it on a permissioned blockchain network, providing greater decentralization and tamper resistance. Many systems combine both routes: did:web for fast onboarding, and distributed anchoring when additional immutability guarantees are required.

The difference from a traditional identity system is significant: each organization owns its own identifier, chooses the DID method best suited to its context, and decides which credentials to associate with it.

How Identity Is Verified Without Relying on a Third Party for Each Transaction

The most practical aspect of this model is that verifying a credential doesn't require contacting the issuer at the moment of the transaction. Broadly speaking, the process works like this:

1. An issuing body or entity issues a verifiable credential to a company, digitally signing it with its own key.
2. The company stores that credential in its identity repository, associated with its DID.
3. When that company wants to join a data space or start a transaction with another participant, it presents the corresponding credential.
4. The verifier checks the credential's digital signature using the issuer's public key, which is publicly queryable, without needing to call the issuer or wait for manual confirmation.
5. If the signature is valid and the credential hasn't been revoked, the transaction can proceed automatically.

This mechanism is what allows a new company's digital onboarding into a data space to be resolved in minutes rather than days. Consider an agri-food services company in Castile and León that wants to join a data space to share traceability information with its distributors. Instead of sending certificates by email and waiting for manual validations, it presents its verifiable credentials associated with its DID, the system automatically checks their validity, and the company is enabled to operate within the data space's trust framework with no further steps required.

What They Offer Over Traditional Certificates in B2B Processes

Compared to the paper or PDF certificates that still dominate much of B2B processes, verifiable credentials bring concrete advantages:

• Instant verification: no need to wait for human confirmation or call the issuer to know whether a certificate is still valid.
• Resistance to forgery: the cryptographic signature makes it unfeasible to modify the credential's content without invalidating it.
• Reusability: the same credential works for multiple verifiers and transactions, without having to request a new document each time.
• Holder control: the company decides which credentials to present to each requester, without exposing more information than necessary.
• Clear revocation: if a credential is no longer valid, the issuer can revoke it, and verifiers detect this on the next check, without depending on the holder voluntarily withdrawing it.

This combination of speed and reliability is what makes verifiable credentials the natural foundation of digital trust within a data space, where transactions between organizations need to be resolved quickly without sacrificing security.

Verifiable Credentials and Agreement Registries: A Complete Trust Layer

In a modern data space, verifiable credentials don't work in isolation — they're integrated with other trust components. Once a participant's identity has been verified through its DID and credentials, the system can record data-exchange agreements through a verifiable registration mechanism, whether on a distributed ledger network or an equivalent system, keeping a traceable record of which organization, with which verified identity, accepted which conditions in each transaction.

This combined layer — verifiable identity plus agreement registration — is what allows two companies that have never met to start exchanging data with reasonable guarantees, without needing a prior trust relationship or a third party manually arbitrating every transaction.

Take the Step Toward a Trusted Digital Identity

If your organization needs to onboard suppliers, clients, or partners into a data-exchange environment quickly and securely, verifiable credentials and decentralized identifiers are the technological foundation that makes this possible without sacrificing control or traceability. A modern data space builds this identity model into its design from the start, combining methods such as did:web with methods anchored on distributed ledger technologies, enabling fast, verifiable digital onboarding for companies and administrations.

If you want to understand how to apply this digital trust model to your organization, look for a technology partner with experience in data spaces who can answer your questions and guide you through the process.