thumb|Kairos relief, copy of Lysippos, in Trogir (Croatia) thumb|Kairos as portrayed in a 16th-century fresco by Francesco Salviati Kairos () is an ancient Greek word meaning 'the exact or critical 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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x41df9d1afa48fbc23c01a4c2b089b6a679af0121caab71d32412031c9a20efec. Chain 2 (Bitcoin): anchored in block 954650 (2026-06-21T04:51:12Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/dad70a1f-6212-45b3-8cc7-e206d358e8e1.json and https://artists.proofprofile.net/proofs/artist/dad70a1f-6212-45b3-8cc7-e206d358e8e1.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).