thumb|upright=1.35|An artist's impression of ice age Earth at Pleistocene glacial maximum An ice age is a term describing periods of time when the reduction in the temperature of Earth's surface and
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 0x33be1095926e4047763e3cab384b3fd95343e712c4aba000ac02b7ec924a8a69. Chain 2 (Bitcoin): anchored in block 954784 (2026-06-22T02:53:59Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/fa1270cd-4e39-4ee4-a233-27bfab61a8e8.json and https://artists.proofprofile.net/proofs/artist/fa1270cd-4e39-4ee4-a233-27bfab61a8e8.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).