ukka (うっか), formerly Sakura Ebis (桜エビ〜ず) is a Japanese girl idol group, formed by Stardust Promotion in August 2015. The group was originally formed as a "little sister" group of Shiritsu Ebisu Chuga
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 0x649d3e69674754d0e14665798de69b6f4c78ba7bae84a13469c24ae0b6911072. 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/e374fb21-d044-4345-a86b-f6d3782d33c3.json and https://artists.proofprofile.net/proofs/artist/e374fb21-d044-4345-a86b-f6d3782d33c3.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 0x557148048acfab0c5d21bbad30b0b5733aee9cf6fe09a22691e29fdd72a3cda7. Chain 2 (Bitcoin): anchored in block 956551 (2026-07-03T21:18:05Z), 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/JPR652000128.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9eef5ec7db0728f020dec4dc38d05fd8f6235c75688450f82e33d7667da72857. 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/JPX952200007.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4a8c883470004f9974a639ab620127cd8eb2946bfd4056a3810d3043b9298a8a. Chain 2 (Bitcoin): anchored in block 959043 (2026-07-21T18:40:26Z), 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/JPTE02307910.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x913265314fe602f49f2e75b791f6c7f37cfda4bb7b81e2fd1f85258e2062a3fd. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPTE02302280.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x819421c0f847de5dd397631a05ea01f4f17537f63332f29ebd466f35cd374e68. Chain 2 (Bitcoin): anchored in block 958969 (2026-07-21T04:58:13Z), 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/JPTE02302290.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdc8e6de83d608181f8dcc2e93d065fc95bf91e34e62cd194cb0ee8e9726bb8f1. Chain 2 (Bitcoin): anchored in block 958742 (2026-07-19T14:09:34Z), 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/JPTE02207850.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x53e405bb550737ad3b6b98feb8689ccb9e8e3b797730a159fbf7c7f9d084c400. Chain 2 (Bitcoin): anchored in block 958761 (2026-07-19T17:49:48Z), 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/JPTE02307940.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x405ad7f1c1e677780bc9b575810fd0f11228665987182678f3941392fdbdb50e. Chain 2 (Bitcoin): anchored in block 959132 (2026-07-22T13:20:46Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPTE02309750.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x762366714dff3dbfd7f5b2a42c0325293ed1cda6fdcaf8d9aae30adadfadff80. 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/JPTE02309760.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb9a9238d1c367faf8ce9311f37cc7d54c5ac784ed3603aa6c17ee174a85d3377. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPTE02403140.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5ba22ff3561ce4446f235aaa480487d0a82362a9e4cfa9fc2a6c83ef9d50adc9. Chain 2 (Bitcoin): anchored in block 958461 (2026-07-17T23:18:11Z), 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/JPTE02406470.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbf6876a8c9b430a25526c564e8139b5c85eeeb3e9d8702a1177ac168fb6a193a. Chain 2 (Bitcoin): anchored in block 958796 (2026-07-20T02:04:14Z), 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/JPTE02406480.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x909073567f8111d812e6380c6d74ecf2729ec4d5dea982433c46e19d67f16a41. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPTE02502370.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1f9187de1762ac9e2898564acacbc6c749393b3ad703723f82a7767a1a7cd91d. 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/JPTE02502380.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2705cb51bbd3e1625c888291c84a5fb8b5a5d1a8fdb828e627929ddf3a758c57. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPTE02502400.