Why does showing my mental-health credential reveal which clinic issued it?

Selective disclosure lets you share a single attribute without exposing your other data, but it cannot hide which institution signed the credential. A presentation from a credential issued by a psychiatric facility, an HIV clinic, or a criminal court tells the verifier something sensitive before a single attribute is shared. The EU Digital Identity Wallet Architecture and Reference Framework mandates issuer-hiding, but a June 2026 technical audit of the wallet finds no deployed mechanism that achieves it. Solutions in the research literature, anonymous credential schemes, issuer-set membership proofs, are incompatible with the SD-JWT and mdoc formats already locked in as the wallet defaults. Every sensitive-domain deployment today ships on a standard that leaks the one thing it was supposed to protect.