What Is Selective Disclosure?

Selective disclosure is the ability to share only the specific information required for a transaction, while keeping everything else private. Instead of handing over an entire credential, you prove just the one fact that matters.

A familiar example is proving your age. To buy a drink, a bartender only needs to know whether you’re over 21. With selective disclosure, you can share exactly that, nothing more, without revealing your name, address, license number, or full date of birth.

The Problem With Physical IDs

Physical IDs overshare by design. When you show a driver’s license, you expose far more information than the situation requires: your full name, home address, exact birthdate, license number, and physical characteristics.

This creates unnecessary risk. Every extra data point can be copied, recorded, or misused for identity theft, stalking, profiling, or surveillance. The transaction only requires one fact, but the system forces an all-or-nothing exchange.

How Selective Disclosure Works

Selective disclosure is built into verifiable digital credentials through the use of cryptography.

When an issuer, such as a DMV, creates a verifiable digital credential, it cryptographically signs the data to ensure its authenticity. That single signature enables the credential holder to later generate proofs that reveal only selected attributes, without compromising the issuer’s original signature.

At a bar, your digital wallet doesn’t send your full credential. Instead, it generates a cryptographic proof that the holder is over 21, for example, that their date of birth is before January 1, 2004.

The verifier checks this proof against the DMV’s cryptographic signature to confirm it’s valid. The result is trust without oversharing: the bartender can visually verify the holder using the photo, while learning only that the age requirement is met, without seeing the holder’s address, full birthdate, or other unnecessary personal details.

The Cryptographic Foundation

Selective disclosure is enabled by cryptographic techniques such as BBS+ signatures, SD-JWTs, or related mechanisms, depending on the credential format and protocol used. These approaches allow a credential to be signed once and selectively revealed many times.

Crucially, the disclosed information is mathematically bound to the issuer’s signature. If someone tried to alter or fake the data, the proof would fail verification. This is why verifiers can trust selective disclosure proofs without needing to see the full credential.

Real-World Examples

Selective disclosure applies far beyond age checks:

• Proving age: Share only “over 21” without revealing your exact birthdate, name, or address.
  
  

• Proving residency: Confirm you live within city limits without exposing your full street address.
  
  

• Professional credentials: Prove you hold a valid license or degree without revealing unrelated personal details or introducing bias.
  
  

• Eligibility checks: Demonstrate you meet requirements, such as not being on a sanctions list, without exposing your entire identity.

The Principle of Minimal Disclosure

Selective disclosure enforces data minimization at the technical level. Verifiers receive what they need, nothing more. Holders maintain control over their personal information.

This shifts identity from an “all or nothing” model to a “just enough” model. Verifying that someone is over 21 is reasonable for the interaction; collecting their address or storing a copy of their ID is not. Selective disclosure makes that distinction enforceable by design, not just by policy.

In practice, it’s one of the most important privacy advances in modern digital identity, and a cornerstone of user-controlled, rights-respecting systems.