thumb|The Tomb of I'timād-ud-Daulah in Agra, India A tomb (from tumbos, meaning "mound" or "burial monument") is a repository for the remains of the dead. It may be above or below ground and can var
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 0xabd4cafb1ba9b51ec9697ff00b5f5322d18ab640ac4347c412c4e7002d7d7433. Chain 2 (Bitcoin): anchored in block 953605 (2026-06-14T07:39:50Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/1138a26b-c5be-42b6-884a-4ab82cf42a83.json and https://artists.proofprofile.net/proofs/artist/1138a26b-c5be-42b6-884a-4ab82cf42a83.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).