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 0xd4e1da3f5c80e95b9a3b99d2b1d9653d083bfc9fc3b77e7aae5a825940e81726. Chain 2 (Bitcoin): anchored in block 954065 (2026-06-17T08:10:43Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/3d79e7e7-b2d6-41f6-8bf5-62b455a107ab.json and https://artists.proofprofile.net/proofs/artist/3d79e7e7-b2d6-41f6-8bf5-62b455a107ab.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
"Festival" 4th Anniversary Session「誰もいない夏」 (Live)
"Festival" 4th Anniversary Session [The Summer of No One] [Live]