Mark or Marc Campbell may refer to: Mark Campbell (defensive tackle) (born 1972), American football player Mark Campbell (tight end) (born 1975), American football player Mark Campbell (footballer) (b
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 0x3bff69662da744b107c1cb81981cbd6e4685314ee703b1886a9ef0a9c4901a11. Chain 2 (Bitcoin): anchored in block 954346 (2026-06-19T03:51:26Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/94b5c45e-502f-4d0f-80ac-c0f879cfb031.json and https://artists.proofprofile.net/proofs/artist/94b5c45e-502f-4d0f-80ac-c0f879cfb031.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).