Andrei Yurievich Sokolov (; romanized: Andrey Yur'yevich Sokolov; born 20 March 1963, in Vorkuta, Komi ASSR, Russian SFSR, Soviet Union) is a Russian chess Grandmaster living in and playing for France
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 0x25b475638e03f9590155a9b09f3d55095fe92a0566c73b96528542b6d58ad53f. Chain 2 (Bitcoin): anchored in block 954342 (2026-06-19T03:22:39Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/91b1408b-d96f-463d-a7e6-5d3ab47bc973.json and https://artists.proofprofile.net/proofs/artist/91b1408b-d96f-463d-a7e6-5d3ab47bc973.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
The Queen of Spades, Op. 68, Act I Scene 1: Scene and Herman's Arioso "Chem konchilas vchera igra?"
Tchaikovsky: The Queen of Spades, Op. 68
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp 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 0xa38c55692290084b2b19aae7f8018799a2b41561daf30f98c12b0a6f934a0698. Chain 2 (Bitcoin): anchored in block 960216 (2026-07-30T06:39:12Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/UK2Y21800849.
The Queen of Spades, Op. 68, Act I Scene 1: Scene and Tomsky's Ballade "Kakaya vedma eta Grafinya"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaef9bfc22cb02ceea9f717f6ac2cdd83d731e8efc55c3f5d692aae600c2e2ea5. Chain 2 (Bitcoin): anchored in block 960187 (2026-07-30T01:34:28Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/UK2Y21800856.
The Queen of Spades, Op. 68, Act I Scene 1: Final Scene "Se non e vero"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbc5ab82e408170983410e488bdaa5237190e6cb282cb61ca9523c547356b05e2. Chain 2 (Bitcoin): anchored in block 960207 (2026-07-30T04:47:22Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/UK2Y21800858.
The Queen of Spades, Op. 68, Act II Scene 3: Scene and Yeletsky's Aria "Hozyain prosit"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x00a7ed861309b53b469ced57151feb4d1c3f0d2840c2f474b0defb46b01d4e1a. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/UK2Y21800872.
The Queen of Spades, Op. 68, Act II Scene 3: Scene "Posle predstavleniya zhdite menya v zale"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5610e2e2c7491c50a445bacf174ae81605de33920440b9597e021e6901385ae9. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/UK2Y21800875.