Selective disclosure via SD-JWT for OB 3.0 / CLR 2.0 wallet interoperability

[t3-atharva]

Brief Description

As an OB 3.0 Issuer and CLR 2.0 certified implementer, we need selective disclosure in JWT-native deployments that interoperate with the broader wallet ecosystem (e.g., OID4VCI / OID4VP flows and eIDAS-aligned wallets). SD-JWT / SD-JWT VC is widely adopted there, but is not currently a certification-supported proof mechanism for OB 3.0. The desired outcome is for SD-JWT to be recognized as an allowed (not required) selective-disclosure proof for OB 3.0 / CLR 2.0, giving issuers a JWT-native option without maintaining a parallel Linked Data proof path.

Use Case Actors

• Issuer — issues OB 3.0 / CLR 2.0 credentials as SD-JWT
• Holder / Wallet — stores the SD-JWT and produces selective disclosures
• Verifier / Relying Party — verifies the SD-JWT presentation
• 1EdTech conformance/certification system — validates the proof mechanism

Pre-conditions

• The credential content maps to the OB 3.0 / CLR 2.0 data model.
• The issuer can produce an SD-JWT (or SD-JWT VC) with selectively disclosable claims.
• The holder uses a wallet capable of SD-JWT presentation (e.g., via OID4VP).

Basic Flow

1. Issuer creates the credential and secures it as an SD-JWT with selectively disclosable claims.
2. Issuer delivers the SD-JWT to the holder's wallet (e.g., via OID4VCI).
3. Holder selects which claims to disclose for a given verifier.
4. Wallet produces an SD-JWT presentation revealing only the selected claims.
5. Holder presents it to the verifier (e.g., via OID4VP).
6. Verifier validates the issuer signature and the disclosed claims.

Post-conditions

• The verifier confirms authenticity and integrity from the disclosed claims alone.
• Undisclosed claims are not revealed.
• The implementation is recognized as conformant for OB 3.0 / CLR 2.0 when using the allowed SD-JWT proof.

Additional considerations

• Companion to our BBS (bbs-2023) use case Unlinkable selective disclosure via BBS (bbs-2023) for OB 3.0 / CLR 2.0 #640; both expand the set of recognized selective-disclosure proofs beyond ecdsa-sd-2023 and can be evaluated together or independently.
• Relates to the "recognize, don't mandate" evolution framework described in PR Clarify proof mechanism and algorithm selection #584, while acknowledging SD-JWT is a different (JWT) proof family.
• Conformance clarification requested: mandatory vs. selectively disclosable claims, and any fields that must remain disclosed.

Requested by

TruScholar, a 1EdTech Member
Contact: Atharva (atharva@truscholar.io)