Trust Assertions
A trust assertion is a signed, context-scoped claim about a subject that can be independently verified.
Assertion vs signal
| Aspect | Trust signal | Trust assertion |
|---|---|---|
| Origin | Derived from events | Issued by attestor |
| Form | Normalized graph node | Signed claim document |
| Typical use | Scoring input | Portable proof export |
| Verification | Provenance walk | Cryptographic signature |
Signals feed the intelligence engine; assertions MAY be exchanged across registry boundaries as portable proofs.
Assertion structure
{
"assertion_id": "asr_7c4d9e2f",
"pti_id": "pti_7f3c9a2b1e",
"context_id": "employment",
"claim": {
"type": "employment.verified",
"employer": "org_pti_abc123",
"role": "field_agent",
"tenure_months": 18
},
"confidence": 0.95,
"evidence_ids": ["evd_3f8a1c2b"],
"issuer_id": "ver_hr_registry",
"issued_at": "2026-04-01T12:00:00Z",
"expires_at": "2027-04-01T12:00:00Z",
"signature": "eyJhbGciOiJFZERTQSIs..."
}
Issuance flow
Verification requirements
Verifiers MUST validate:
- Signature algorithm and public key from issuer trust store
issued_at/expires_atwindowpti_idstill active and not suppressed- Issuer entitled for
context_idand claim type
Failed verification MUST return PTI-4222.
Federation
Cross-operator assertion exchange uses signed envelopes per Interoperability Specification. Receiving registries MAY import assertions as read-only graph edges without re-signing.
Revocation
Assertions MAY be revoked before expires_at via:
- Revocation list published by issuer
- Registry suppression event
- Subject dispute upholding retraction
Revoked assertions MUST NOT appear in new trust reports.
Trust Passport linkage
Portable proof bundles (sometimes called a Trust Passport) aggregate multiple assertions and recent context summaries for subject-controlled sharing. Passports SHOULD include verify URIs for each constituent assertion.