upright=1.35|thumb|Taking of Jerusalem by the Crusaders. Year 1099 (MXCIX) was a common year starting on Saturday of the Julian calendar. Events By place First Crusade January 16 – The Crus
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 0x8d9df570efd74f53f1a5f6955e173feea276f0335e04619e46ce89a3d7bf4f02. Chain 2 (Bitcoin): anchored in block 954065 (2026-06-17T08:10:43Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/4a0616c2-b5cf-4a98-a37b-c6280f123f39.json and https://artists.proofprofile.net/proofs/artist/4a0616c2-b5cf-4a98-a37b-c6280f123f39.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).