Florence Arthaud, (28 October 1957 – 9 March 2015) was a French sailor. In 1990, she became the first woman to win the Route du Rhum. She died in a helicopter crash in the Argentine province of La Ri
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 Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xecafdd7f596650ba21eb55e7efcd015dcc83b165cdf430b931f08e9b9cc1d184. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/7a972951-4c89-4e68-a3e5-c34a3c02c094.json and https://artists.proofprofile.net/proofs/artist/7a972951-4c89-4e68-a3e5-c34a3c02c094.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.