Zag or ZAG may refer to: Places Zag, Kentucky, US Zag, Mongolia, a district Zag, Morocco, a town Zagreb Airport, Croatia IATA airport code People Zag de Sujurmenza, 13th-century Spanish astronomer Z
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 0x67a0f1d60a3be8882fa8acb3baa4ee45b6a7b22a80b82b7e60c53bdf14f01476. Chain 2 (Bitcoin): anchored in block 953857 (2026-06-15T23:34:38Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/031f862d-81aa-4502-af35-990a5b1b21dc.json and https://artists.proofprofile.net/proofs/artist/031f862d-81aa-4502-af35-990a5b1b21dc.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).