Mavrin () is a Russian masculine surname, its feminine counterpart is Mavrina. It may refer to: Sergey Mavrin (born 1963), Russian heavy metal musician Sergey Mavrin (judge) (1951–2025), Russian judge
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 0xf25fbc961e1746088314e0c7b5ce1647b076bd1cf400b2f856bf3100b0c53cb1. Chain 2 (Bitcoin): anchored in block 953996 (2026-06-16T20:04:35Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/2fe516df-e633-477b-abfb-9c167ac08fb8.json and https://artists.proofprofile.net/proofs/artist/2fe516df-e633-477b-abfb-9c167ac08fb8.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).