Samantha Cook (born 10 November 1987) is a Brazilian jiu-jitsu black belt competitor. Cook is a No-Gi World champion, a four-time European champion and a four-time British champion in coloured belts.
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 0x80841c95182335103eeebe489222025ffbdaba7b25e3fed2e0970b540f20abac. Chain 2 (Bitcoin): anchored in block 954717 (2026-06-21T15:47:51Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/f5d2e81b-b753-4d0b-a15c-0fc02dc34c83.json and https://artists.proofprofile.net/proofs/artist/f5d2e81b-b753-4d0b-a15c-0fc02dc34c83.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).