Marq or MARQ may refer to: People Given name Marq Cerqua (born 1977), American former National Football League player Marq Mellor (born 1968), American field hockey player Marq Porciuncula (born 1
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 0xc32185fe70f5fb57c7d2ccb81a6ac2704de55bc148f4ec1b2e03dd6f789168ea. Chain 2 (Bitcoin): anchored in block 954500 (2026-06-20T04:47:29Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/9cb218f0-67ec-4b84-8045-6f92cacde37b.json and https://artists.proofprofile.net/proofs/artist/9cb218f0-67ec-4b84-8045-6f92cacde37b.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).