The WICG spec doesn't mention this at all, but it seems like Google plans to restrict the set of allowed issuers. From <https://www.chromium.org/updates/trust-

The WICG spec doesn't mention this at all, but it seems like Google plans to restrict the set of allowed issuers. From <https://www.chromium.org/updates/trust-token> https://www.chromium.org/updates/trust-token>: > Process for registering as an issuer: https://docs.google.com/document/d/1cvUdAmcstH6khLL7OrLde4TnaPaMF1qPp3i-2XR46kU/ https://docs.google.com/document/d/1cvUdAmcstH6khLL7OrLde4Tn... which says: To apply for an Issuer (and its key commitments) to be included within Chrome, the Issuer’s operator must file a new bug on the Chromium Issue Tracker, and provide: * Issuer Name - Human readable name representing the Issuer. * The origin that is used for the issuing service (scheme, host, port). The scheme must be HTTPS. * An email or email alias that is monitored by the Issuer’s operator for issues regarding the Issuer. * A public HTTPS endpoint that responds to key commitment requests. * A description of the Issuer, describing its intended purpose.