STEF (formerly STEF-TFE) is a European specialist in cold logistics for temperature-sensitive and agro-food products. STEF is active in 7 European countries: Belgium, Spain, France, Italy, the Nethe
1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6062d29b3d02c8861d49bac78745e539379c5a2f1adcb55d0852df8d147d302f. Chain 2 (Bitcoin): anchored in block 954346 (2026-06-19T03:51:26Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/991b4939-351d-4f53-bcdd-82e7139bf49c.json and https://artists.proofprofile.net/proofs/artist/991b4939-351d-4f53-bcdd-82e7139bf49c.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).