thumb|Marc Bernard in 1934 Marc Bernard (6 September 1900 in Nîmes – 15 November 1983 in Nîmes), was a French writer, the winner of the French literary prize Prix Interallié for Anny in 1943 and of t
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 0x8c874ddb447de8fa85e4e304bfad5299eb1346059a8a10690a6f0039ad47c445. Chain 2 (Bitcoin): anchored in block 954742 (2026-06-21T20:46:40Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/fd623a86-dbb7-4496-aefc-8c01dd43cf60.json and https://artists.proofprofile.net/proofs/artist/fd623a86-dbb7-4496-aefc-8c01dd43cf60.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).