Sajou no Hana (stylized as sajou no hana) is a Japanese rock group signed to Kadokawa and Warner Bros. Japan. It is composed of vocalist Sana, with founder and keyboardist and bassist Tatsuya Kitani
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 0x15388048812be884881226995b63bf11266c5b00316e1b67c6ff3dba2809a925. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/6b39952d-fc0f-4892-b0ab-9efe05e1f7b4.json and https://artists.proofprofile.net/proofs/artist/6b39952d-fc0f-4892-b0ab-9efe05e1f7b4.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
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 0xcc16e7c85d1ffd18d78118a34f203f0175d7ef0adc27f6e78961c82c772986dc. Chain 2 (Bitcoin): anchored in block 958366 (2026-07-17T04:59:09Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPQ461800413 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb0565d1ed911f85a5f7b6d4e55c0f0a4f6c1cae9c997cac3dc6eed279540e765. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPQ461800414 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x58db830b901e2fc6298af835e8c35f59e06f24cec6d9f75db6717c8ed86a1270. Chain 2 (Bitcoin): anchored in block 956891 (2026-07-06T07:16:32Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPQ461800415 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xafead843ded2d424e337d6bd5ce1a76629a1e9e40ddfcda1737b228a0be1c6a5. Chain 2 (Bitcoin): anchored in block 958975 (2026-07-21T06:12:52Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPQ461800668 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x69aa1e8533d531e23952457cff8c19835f86ce156989f4cc0222c2ec3f86a189. Chain 2 (Bitcoin): anchored in block 958468 (2026-07-18T00:27:51Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPQ461800669 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdc9e80c0bf892a5e6651c6a0d1c20aadfce198c1fad200323fce13d20692035c. Chain 2 (Bitcoin): anchored in block 956822 (2026-07-05T18:48:28Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPQ461800670 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x775001e31dbadf15152b91f4681b5431449dca8d96b49e2072d9aeb6a0489e4a. Chain 2 (Bitcoin): anchored in block 958980 (2026-07-21T07:04:12Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPQ461900359 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xca469a560c920d6a69c6edd0ba964aae39edaf118aab3be3cfbe6a46c7595e2b. Chain 2 (Bitcoin): anchored in block 959096 (2026-07-22T03:48:36Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPQ461900360 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa03fe51ff99096611a46cac4e8364725bce2e2239c08c843718337a6745cf163. Chain 2 (Bitcoin): anchored in block 958796 (2026-07-20T00:01:46Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPQ462000123 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd8808a1eebf6e6e8037dffc745a967cce043c2852b8ee1f3e862ee58dbcafd62. Chain 2 (Bitcoin): anchored in block 957770 (2026-07-12T23:17:00Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPQ462000187 — a six-check JSON result.
OPENING THEME FROM TV SERIES "IS IT WRONG TO TRY TO PICK UP GIRLS IN A DUNGEON? IV" TENTO
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x194a52b5b124f3eb43ecdee70ce870c20cf9c1236f3ab504d7742598f3e8e549. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPD732200167 — a six-check JSON result.
TVアニメ「ダンジョンに出会いを求めるのは間違っているだろうかⅣ 新章 迷宮篇」オープニングテーマ「天灯」
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x194a52b5b124f3eb43ecdee70ce870c20cf9c1236f3ab504d7742598f3e8e549. Chain 2 (Bitcoin): anchored in block 956742 (2026-07-05T05:07:15Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPD732200167 — a six-check JSON result.
TV SERIES ”IS IT WRONG TO TRY TO PICK UP GIRLS IN A DUNGEON? IV”
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xff8295e8184f983b9e3241f4c72bb280cd167a5ddc18d94b6e40aecc5396bf8f. Chain 2 (Bitcoin): anchored in block 957834 (2026-07-13T09:42:16Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPD732200489 — a six-check JSON result.
TVアニメ「ダンジョンに出会いを求めるのは間違っているだろうかIV 深章 厄災篇」エンディングテーマ「切り傷」
ENDING THEME NUISANCE FROM TV SERIES ”SPY CLASSROOM” 2ND SEASON
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x202b561079303e0d852484ea70c70a3e28810c23066f6719383c9bdcfb42323d. Chain 2 (Bitcoin): anchored in block 956822 (2026-07-05T18:48:28Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPD732301015 — a six-check JSON result.
TVアニメ「スパイ教室」2nd season エンディングテーマ「ニューサンス」
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x202b561079303e0d852484ea70c70a3e28810c23066f6719383c9bdcfb42323d. Chain 2 (Bitcoin): anchored in block 956772 (2026-07-05T10:01:46Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPD732301015 — a six-check JSON result.
TVアニメ「異修羅」オープニングテーマ「修羅に堕として」
SHURANI OTOSHITE OPENING THEME FROM TV SERIES ”ISHURA”
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc725f916ca1a4e21b178747d858ea45a5f9afd584bd60c5cab1692962a78dd0f. Chain 2 (Bitcoin): anchored in block 958208 (2026-07-15T22:40:25Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPD732400002 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc725f916ca1a4e21b178747d858ea45a5f9afd584bd60c5cab1692962a78dd0f. Chain 2 (Bitcoin): anchored in block 959011 (2026-07-21T13:26:15Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPD732400002 — a six-check JSON result.