From Physical Pathology to Smart Contract State: Structuring QFER Data

1. The Transduction Problem in RWA Physical Oracles

Traditional Decentralized Oracles (such as Chainlink or Pyth) are designed for digital-to-digital transduction—fetching financial API data streams and computing median price feeds. However, Real-World Asset (RWA) verification requires physical-to-digital transduction: converting non-digital material conditions (such as concrete pathology, hull thickness, or legal encumbrances) into machine-readable inputs.

Without a standardized data payload, smart contracts cannot parse physical inspection reports. The Prop Trust Verified Standard (PTVS v1.0) solves this by defining the JSON-LD schema for Qualified Forensic Evidence Records (QFER) sealed under eIDAS 2.0 Qualified Electronic Signatures (QES).

2. Canonical QFER JSON-LD Schema Structure

Every inspection performed by a Prop Trust Certified Expert (PTCE) generates an immutable QFER payload. The schema maps metrological parameters, cryptographic hashes, and legal validity into a unified structure:

{
  "@context": "https://forensics-oracle.org/schemas/v1/qfer.jsonld",
  "@type": "QualifiedForensicEvidenceRecord",
  "header": {
    "qferID": "QFER-2026-ES-0161-MAR-0892",
    "timestamp": "2026-11-04T08:30:00Z",
    "rfc3161TimestampToken": "BASE64_ENCODED_TSA_RESPONSE"
  },
  "perito": {
    "officialRegistration": "Exp. 0161 (Spain)",
    "orcid": "https://orcid.org/0009-0007-5824-3602",
    "eIDAS_QES_Fingerprint": "SHA256:7f8a9b...3c2a"
  },
  "assetPhysicalIdentity": {
    "assetType": "MaritimeVessel",
    "geospatialCoordinates": "38.1691° N, 0.4697° W",
    "cadastralOrIMO": "IMO-9823411",
    "physicalHash": "SHA256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
  },
  "diagnosticResult": {
    "structuralIntegrityPass": true,
    "pathologyDetected": false,
    "ndtMethodsUsed": ["UltrasonicThickness", "InfraredThermography"],
    "isPhysicallyAndLegallyBound": true
  }
}

3. Interfacing with ERC-3643 Identity Registries

The ERC-3643 standard utilizes an IdentityRegistry to validate whether an address is eligible to hold or transfer permissioned RWA tokens. PTVS v1.0 injects QFER validity checks directly into the compliance verification loop via custom Claim Topics.

Before any transfer is executed on-chain, the ERC-3643 Compliance contract queries the PTVS Physical Oracle Interface:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

interface IPTVSPhysicalOracle {
    function verifyQFER(
        bytes32 assetPhysicalHash,
        bytes32 qferPayloadHash,
        bytes memory eIDAS_Signature
    ) external view returns (bool isBound, uint256 validUntil);

    function isPhysicallyAndLegallyBound(bytes32 assetPhysicalHash) external view returns (bool);
}

contract PTVSERC3643Compliance {
    IPTVSPhysicalOracle public immutable oracle;

    constructor(address _oracleAddress) {
        oracle = IPTVSPhysicalOracle(_oracleAddress);
    }

    function canTransfer(
        address _from,
        address _to,
        uint256 _amount,
        bytes32 _assetHash
    ) external view returns (bool) {
        // Enforce Layer 0 physical verification before allowing Layer 2 transfer
        if (!oracle.isPhysicallyAndLegallyBound(_assetHash)) {
            return false; // Trigger RFC-003 circuit breaker
        }
        return true;
    }
}

4. The RFC-003 ‘Hollow Token’ State Machine

If a PTCE auditor issues a QFER update marking isPhysicallyAndLegallyBound = false (e.g., due to uncorrected structural pathology or court freeze orders), the Oracle contract executes a state mutation:

1. The internal mapping assetBindingState[_assetHash] updates to false.
2. The event TokenHollowed(bytes32 indexed assetHash, string reason) is emitted.
3. Subsequent calls to canTransfer() across all connected ERC-3643 tokens evaluate to false, executing the freezeByLegalMandate() primitive automatically.

5. Conclusion & Specification Availability

By formalizing the JSON-LD payload and integrating directly with ERC-3643 identity registries and Solidity compliance interfaces, PTVS v1.0 guarantees that smart contract state transitions remain strictly synchronized with sworn off-chain physical diagnostics.