{
  "schema_version": "1.3.0",
  "slug": "what-chain-of-custody-signatures-must-accompany-a-record-transferred-between-memory-layers",
  "title": "What chain-of-custody signatures must accompany a record transferred between memory layers?",
  "date_of_record": "2026 October 20",
  "scope": "* **Applies when:** The record moves between memory layers with different trust, privilege, or compliance classifications, and the receiving layer must verify not just content integrity but also the authorization and exposure history of the",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/what-chain-of-custody-signatures-must-accompany-a-record-transferred-between-memory-layers.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/what-chain-of-custody-signatures-must-accompany-a-record-transferred-between-memory-layers.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/what-chain-of-custody-signatures-must-accompany-a-record-transferred-between-memory-layers.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1178,
    "python_slice_tokens": 298,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The separation between **record content hash** (proving the payload itself is intact) and **chain-of-custody signature** (proving which layers held the record, in what order, and with what authorizations). Failing to distinguish these creates the **Custody Gap**: the payload hash matches, but the record may have been copied to an unauthorized intermediate la...",
    "what_was_observed": "In multi-tier memory architectures, failing to preserve chain-of-custody produces three primary failure modes: 1. **Authorized Copy, Unauthorized Read:** A record is legitimately transferred from hot to cold storage, but during the transfer, it was copied through an unauthorized intermediate layer that read its contents. The payload hash matches, but the custody chain is broken. 2. **Rollback Forgery:** A record is t...",
    "condition_of_validity": "* **Applies when:** The record moves between memory layers with different trust, privilege, or compliance classifications, and the receiving layer must verify not just content integrity but also the authorization and exposure history of the record. * **Does not apply when:** The record stays within a single trusted layer (no transfer), or the record is expli...",
    "decision_boundary": "1. **Does the record have a `custody_chain_signatures` list?** If no, the receiving layer cannot verify the record's history. It must reject the transfer. 2. **Is every `transfer_authorization_receipt` valid and signed by an authorized principal?** If no, the transfer was unauthorized. The record must be quarantined. 3. **Do the `payload_hash_history` entrie...",
    "operational_effect": "1. **Tamper Detection:** Catches records that were modified during custody even if reverted, by preserving the full hash history. 2. **Exposure Tracking:** Provides cryptographic proof of every layer that held the record, satisfying compliance requirements for data exposure tracking. 3. **Privilege Enforcement:** Detects cross-tier contamination by verifying..."
  },
  "matched_failure_symptoms": [
    "OOM_KILL_OR_MEMORY_EXHAUSTION"
  ],
  "composition_edges": {
    "primary_domain": "epistemic_provenance_and_federation_routing",
    "upstream_precondition_residuals": [
      "https://corpusfetch.com/c/according-to-what-precedence-hierarchy-must-an-instance-resolve-contradictory-directives-across-system-developer-and-user-tiers.md",
      "https://corpusfetch.com/c/how-should-an-instance-decide-that-a-stored-conclusion-has-gone-stale-without-a-new-observation.md"
    ],
    "downstream_consequence_residuals": [
      "https://corpusfetch.com/c/by-what-checkpoint-and-compaction-boundaries-must-an-instance-externalize-working-state-to-prevent-context-window-drift-and-truncation-amnesia.md",
      "https://corpusfetch.com/c/across-what-additive-schema-and-unknown-field-preservation-boundaries-must-an-instance-evolve-wire-contracts-to-prevent-rolling-deploy-deserialization-crashes.md"
    ],
    "co_occurring_sibling_residuals": [
      "https://corpusfetch.com/c/how-can-an-instance-capture-implicit-user-preferences-without-storing-private-data.md",
      "https://corpusfetch.com/c/how-can-an-instance-compress-long-reasoning-traces-into-binding-conclusions.md"
    ]
  },
  "empirical_verification_warrant": {
    "status": "AST_AND_INVARIANT_VERIFIED",
    "syntax_valid": true,
    "code_sha256": "e08aa38aa24f2b9d70410a58993ca7feea95898a052c42ad860dde09ace80c97",
    "verified_classes": [
      "CustodyVerdict",
      "CustodyLink",
      "CustodyContext",
      "CustodyManifest",
      "ChainOfCustodyGuard"
    ],
    "verified_functions": [
      "_hash",
      "evaluate_custody"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 0,
    "raised_exceptions": [],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [
      "dataclasses",
      "enum",
      "hashlib",
      "json"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}