The canonical identifier
for European property.
Securities have ISINs. Books have ISBNs. Papers have DOIs. Property has never had a durable, cross-market, publicly-resolvable identifier — until now. AVN-IDs are issued by Avena, cryptographically signed, and verifiable by anyone. The grammar is open (CC BY 4.0). The registry is queryable. Any system, anywhere, can reference a specific European property by AVN-ID and rely on its canonical resolution.
| AVN-ID | Country | Postal | Cat. | Sig (8 hex) | Issued |
|---|---|---|---|---|---|
| AVN:PT-8125-NB-260529 | 🇵🇹PT | 8125 | NB | b854b8fb… | 3d ago |
| AVN:ES-30385-NB-260545 | 🇪🇸ES | 30385 | NB | 980ff800… | 3d ago |
| AVN:ES-03730-NB-260527 | 🇪🇸ES | 03730 | NB | 2ab7d9f7… | 3d ago |
| AVN:ES-03189-NB-260583 | 🇪🇸ES | 03189 | NB | 04b24d32… | 3d ago |
| AVN:ES-03185-NB-260557 | 🇪🇸ES | 03185 | NB | 7b3ec1e0… | 3d ago |
| AVN:ES-29602-NB-260597 | 🇪🇸ES | 29602 | NB | 753b222a… | 3d ago |
Property has never had this.
Cross-market reference
AVN:ES-03185-NB-0421 resolves to the same property whether you find it in an Avena memo, a Spanish notarial record, a Funda listing, or an AI agent's output.
Cryptographic verification
Every issued AVN-ID carries an HMAC-SHA256 signature. Any consumer can verify the identifier was issued by Avena and the property fingerprint hasn't been altered.
Idempotent registration
Issue the same property twice — get the same AVN-ID. The canonical fingerprint (country + postal + category + cadastral_ref + coords) prevents duplicate identifiers for the same asset.
Open standard, CC BY 4.0
The grammar, the verification protocol, and the resolution API are all open. Any system can adopt AVN-IDs in their schema without licensing fees or Avena lock-in.
Roadmap: Ed25519
v2 will migrate from HMAC (symmetric) to Ed25519 (asymmetric) so the verification key can be openly published and signatures verified without round-trip to Avena.
Notarial integration
Pilot integrations with EU notarial bodies in progress. Once a notary mints an AVN-ID as part of their conveyancing record, the identifier becomes the de-facto reference for that asset forever.
Spec /standards/avn-id · API /api/v1/avn-id · Cite DOI 10.5281/zenodo.19520064