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 0x75bf9f03d8810ead92a53cbcc902153023242bec9ec32f5e6bf62cdaabb4c0a7. 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/51523722-78e2-40a3-912a-c62fd8007d8e.json and https://artists.proofprofile.net/proofs/artist/51523722-78e2-40a3-912a-c62fd8007d8e.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Daijobu, Mada Kurutteru (feat. GUMI & KASANE TETO)
Anata_no Tonari_ni Watashi_wa Iruno? (feat. GUMI & KASANE TETO)
Soba_ni Iruyo (feat. GUMI, Una Otomachi & KASANE TETO)
Kimi_no Koe_wo Kikitai (feat. GUMI, Una Otomachi & KASANE TETO)
Kokoro Kui (feat. GUMI, Una Otomachi & KASANE TETO)
Sorani Ochiru (feat. GUMI & Una Otomachi)
pp-pp Den'pa Hasshin'chu (feat. GUMI & Una Otomachi)
Ryukousei Sen'bou (feat. GUMI & Una Otomachi)
Futari Sekai (feat. GUMI & Una Otomachi)
Rida!! (feat. GUMI, KASANE TETO & Una Otomachi)
Hero wa Owaranai (feat. GUMI & KASANE TETO)
Watashi wa Anata no Uso (feat. HATSUNE MIKU)
Aishiteitano wa Uso desuka? (feat. GUMI)