Zhang Haochen () (born June 3, 1990) is a Chinese pianist. He was a Gold Medalist of the 13th Van Cliburn International Piano Competition in 2009, becoming one of the youngest winners in the history o
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 0x548d27a2042ab0e4bb97e865f359d974c47098fe1b0837c11b56e16f53d134f1. 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/f52f27b0-6d4f-4ce0-8a88-a2bbc1df7659.json and https://artists.proofprofile.net/proofs/artist/f52f27b0-6d4f-4ce0-8a88-a2bbc1df7659.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
2009 Van Cliburn International Piano Competition: Preliminary Round - Haochen Zhang
2009 Van Cliburn International Piano Competition: Final Round - Haochen Zhang
Schumann, Liszt, Janáček & Brahms: Piano Works
Tchaikovsky: Piano Concerto No.1 - Prokofiev: Piano Concerto No. 2
Piano Concerto No. 1 in B-Flat Minor, Op. 23, TH 55: I. Allegro non troppo e molto maestoso
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 0x7ba50b9826b11869fb4422d0f8c2fce04c25e71422ee7a10218d4474e24c8f55. 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/SEAEY1981050.