is a Japanese doujin music circle founded by metal composer Keisuke Kurose and mangaka/illustrator Kachiru Ishizue in the end of 2018. History The music circle Elfensjón was formed in the end of 2
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 0xd622cacd13cb4233b7112f668bd2abbc1c1a0bc80abb8f792f04ac16eb76a407. 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/13c87c0c-81f7-4d6e-8b8a-d3322210f7a3.json and https://artists.proofprofile.net/proofs/artist/13c87c0c-81f7-4d6e-8b8a-d3322210f7a3.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
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 0x0da7d7b079bdaad4c1981bc40fa80f5c420a1f017207e4ec68e15866e1c5baf2. Chain 2 (Bitcoin): anchored in block 959109 (2026-07-22T07:21:40Z), 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/JPV751901466.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8b2eb901301c9373d186c20044f69831be71c27923384d406c46f0db55f67496. Chain 2 (Bitcoin): anchored in block 959103 (2026-07-22T05:56:21Z), 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/JPV751901469.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5d854c22e0da3363bcd7bbd7a9c9dde7b98da3d9ec9529a7b0213122d6d9ede2. Chain 2 (Bitcoin): anchored in block 958444 (2026-07-17T19:12:23Z), 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/JPV751901465.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8b8ab0c7a52aa82caf73f7b33d06b60a0bd423dc656a68cdaf0d777613d4d155. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/JPV751901467.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd14c486546b7d1a94b74c4a5211ccb0438a21bf225f08eedb1af41629d4ad64c. Chain 2 (Bitcoin): anchored in block 958600 (2026-07-18T19:24:05Z), 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/JPV751901468.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8b2eb901301c9373d186c20044f69831be71c27923384d406c46f0db55f67496. Chain 2 (Bitcoin): anchored in block 957705 (2026-07-12T12:50:42Z), 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/JPV751901469.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x613f3e4406de0a8678fd0de6f699c66591792b1972ed03b82834487a31b7fa69. Chain 2 (Bitcoin): anchored in block 958596 (2026-07-18T18:42:38Z), 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/JPV751901470.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0456e53d0a1210df14249e03b15ba1b63298698cb8395e5a57c1c5aca40d3c36. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/JPV751901478.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x71f9a4add619dcdf095cb76f373a8b1150554fcf033841426e518030630a8449. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPV751901479.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdf9e852b37b9061f961d20db47ca5fe5dc9d9b8f6ba2b27fd49d248e524a8e3c. Chain 2 (Bitcoin): anchored in block 958251 (2026-07-16T06:29:25Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPV751901473.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x789a39ffa40db83b793ccbc0e8acf5841533b34a0d2fefc95eaffe7a0e667820. Chain 2 (Bitcoin): anchored in block 958063 (2026-07-14T21:07:34Z), 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/JPV751901474.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xda3ed498e9782b5b0d293bdf1342295920ae75a2369dc1e1e98d488c5f627ab9. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPV751901475.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe5523095374dcb1a09bd9c251032b39291c294f2db1192d647364db348b23f81. Chain 2 (Bitcoin): anchored in block 958157 (2026-07-15T13:14:32Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPV752003411.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1e0c3ad4ee3a80674d8b77fe1ddeee32fdcdd475406c4075b6ac9ef5f1b2074a. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPV752003412.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5076c6b17f7a984498f23327006ad0ed36a1b38b3ea5ce4e3955c128f6f2bd50. Chain 2 (Bitcoin): anchored in block 958058 (2026-07-14T20:20:34Z), 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/JPV752003413.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfe55962a299d5b096ca2e7ea90783acbad1ec42fb104402f5da172c6f4832306. Chain 2 (Bitcoin): anchored in block 958357 (2026-07-17T03:33:42Z), 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/JPV752003414.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcffaca5d4e31d02f873c8c023513adb7640f2cd7d01fcf71805fb3cf558d2d5c. Chain 2 (Bitcoin): anchored in block 956725 (2026-07-05T01:12:41Z), 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/JPV752003415.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2198a3524ef9bba8b18789a69471d4d1db90fe6b443d8d451203c739a690d427. Chain 2 (Bitcoin): anchored in block 958480 (2026-07-18T02:58:58Z), 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/JPV752003416.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x02246fa65fbe3df02f67f1ab0b633c4f9b295cda02065763152aade099f6ea89. Chain 2 (Bitcoin): anchored in block 958063 (2026-07-14T21:07:34Z), 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/JPV752003417.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8fcf20af0625ed18f5493e3fa05fd0c64d39b161045492bb706bbe7e38fc0bc4. Chain 2 (Bitcoin): anchored in block 958063 (2026-07-14T21:07:34Z), 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/JPV752003418.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe6ab7591dae103ce104885e5edcb60b252652068d598bdf41cc72c1cf7871dd1. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPV752003419.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd6312e35e6256ad9f98dceb4a626f9e379384f762c3fb19fee0a7ff79c08979c. Chain 2 (Bitcoin): anchored in block 959065 (2026-07-21T22:00:50Z), 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/JPV752003420.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5c83fa87deb06ecb960b977dfd3d453386460e2268159327bb6cfb55c99c846b. Chain 2 (Bitcoin): anchored in block 956857 (2026-07-06T01:26:17Z), 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/JPV752003423.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2c4414ef43d2514ad4ade8620bc43c4207db5113b786cd5f6e659a528c6849cb. Chain 2 (Bitcoin): anchored in block 959054 (2026-07-21T20:19:31Z), 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/JPV752105140.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4b5b4de1e30087ffecf0dd7a1ea248f77bcbbfb50f88c805c3741bfddd77484b. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPV752105162.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8e92c057d0584ef1dedbe3fab6e75ae37e58c0d9c3e6acde78e1dc87551985c6. Chain 2 (Bitcoin): anchored in block 958211 (2026-07-15T23:24:33Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPV752105292.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaffe3d6c866c6701df02da1947edcc29fbcbbbd2b9d3f8783c0fbcc08711f427. Chain 2 (Bitcoin): anchored in block 957709 (2026-07-12T13:52:43Z), 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/JPV752105293.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb8e2e0c0d7595c0e4e6a4ced00080e76d89ce34d8c39372a3ec4fdd8d77799a9. Chain 2 (Bitcoin): anchored in block 958202 (2026-07-15T21:23:21Z), 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/JPV752105294.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4b6bffb38f000646aaab5c0fc366bc3b4e788a1266702700cda1ff583c8e89e2. Chain 2 (Bitcoin): anchored in block 958069 (2026-07-14T21:37:55Z), 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/JPV752307749.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4738a035c286173b064580c94c8f97fa4380409c9b88430845ce6b4b4867f547. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/JPV752307750.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8a4d7cae8e7ee077117d77f67a28f803f8ce6ba4bff054596356d8bf672f8094. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPV752307751.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcbfd637332bddb927f93b78a3e60996cf7b39ac050b72acbae698ea7eed68f9e. Chain 2 (Bitcoin): anchored in block 956375 (2026-07-02T16:51:38Z), 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/JPV752307752.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd389387ea5a2846ec3a1b02c4ed7b3c8d5ccb46882cba059c3541cc99a71a5a2. Chain 2 (Bitcoin): anchored in block 958063 (2026-07-14T21:07:34Z), 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/JPV752408361.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb7640c0831704511b89d9221276a0be4f0d5882f6c4e3e818d913358657a8ff0. Chain 2 (Bitcoin): anchored in block 957709 (2026-07-12T13:52:43Z), 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/JPV752408448.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4e6cecd9fed917c2766d6e2017d1f4cdcc27d24e8fc99f620b4b47f1fb40c8fc. Chain 2 (Bitcoin): anchored in block 957851 (2026-07-13T11:26:33Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPV752408450.
TVアニメ「なぜ僕の世界を誰も覚えていないのか？」エンディングテーマ「UMBRA」
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1ad6424f00641781451af5b9e95211bf9861f138bb74c610d91b3b46e7faa334. Chain 2 (Bitcoin): anchored in block 956856 (2026-07-06T01:25:57Z), 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/JPV752409171.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x853fa5d6eb197a97d4721b4942edaba51677486ef3a4a3bcc3db92e6cc5f04c7. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPZ922001542.