upright=1.5|thumb|Large menhir located between Millstreet and Ballinagree, County Cork, Ireland thumb|The Caramujeira Menhir, currently preserved at the Silves Municipal Archeology Museum, in Portugal
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 0x6a4fa4228a19151c164a4c0a7837180a64f19d938af3a5c4cb779ea76f582cd2. Chain 2 (Bitcoin): anchored in block 953657 (2026-06-14T16:43:25Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/4c592200-228a-4b30-89f8-d9ac0f12eb67.json and https://artists.proofprofile.net/proofs/artist/4c592200-228a-4b30-89f8-d9ac0f12eb67.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).