Los Vikings (also known as Los Vikings de Usulután) are a rock group from Usulután, El Salvador, formed in the 1960s, and are often cited as the exemplary group of the "golden age of Salvadoran rock".
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 0x8ee328e55f099592e6a3ec848d6c165f0b88c999d5d2f4a8ca376cae5f59cb67. 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/d9e6ec4e-0cf4-4371-b0ef-9fec19ff3293.json and https://artists.proofprofile.net/proofs/artist/d9e6ec4e-0cf4-4371-b0ef-9fec19ff3293.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 0x1c2350fdbaf6356367e5880d6380ed4042c9d9d174aaacb5143be26fea927ee8. Chain 2 (Bitcoin): anchored in block 958390 (2026-07-17T09:35:49Z), 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/USJ3V0639507.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x55ebe07c11c1c28e6ad3d8bd48c4a9bb146e2866744675e81ecd0b6e85b29dea. Chain 2 (Bitcoin): anchored in block 958341 (2026-07-17T01:08:10Z), 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/USJ3V0639508.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8073dfbda5a8c610f0a1a167459df1c8fefe6ce0cc296c9b0f5038e4bb379e5d. 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/USJ3V0639509.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x143b8b2c331f896632e625882cf3f5d36bc51896e4885c49a95d038482e48102. Chain 2 (Bitcoin): anchored in block 958484 (2026-07-18T03:34:53Z), 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/USJ3V0639510.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x533835339b4eedf349583bd8aa4db5369d0962626d4721dd83b3e58c04e67004. 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/USJ3V0639511.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x998d0ec38c3036ba0c49ea5c3410ef01b673a8b87f4650af0713259b2a5bbea3. 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/USJ3V0639512.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0294480e0f7a70043943f0f4bfeb019c8a73b72dc977c5d98ff1e46676659f5c. 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/USJ3V0639513.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x632ba869d93bc13e10afc11ddef8e9d62d71ec3e2838d6ceec188b08e7e7a174. 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/USJ3V0639515.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0173e5d90deeb506831b4aee2fcf64fcaf1c4453c2fc3c2f342d58461f68693a. Chain 2 (Bitcoin): anchored in block 959100 (2026-07-22T05:29:55Z), 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/USJ3V0639516.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x17a88a9e77b29151f7ba5be4a98db53a39928b648937e71df38265e9851c2e2f. Chain 2 (Bitcoin): anchored in block 959002 (2026-07-21T11:47:29Z), 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/USJ3V0639518.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4db9d39615fdd4eb8faf5a89005a30943f93b00109f799c965b87f266492b2b2. Chain 2 (Bitcoin): anchored in block 958897 (2026-07-20T14:57:46Z), 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/USJ3V0639519.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xff00e24ef11935b84d1503b137f37f065e94f0d66b9009f41fd0913f871f8e26. Chain 2 (Bitcoin): anchored in block 959023 (2026-07-21T15:22:58Z), 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/USJ3V0639520.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc4a9a0b009aa1453c6d07d22c91a1340f8bf02a5ff494b96113962cc331fc01c. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USJ3V0639522.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf5f5417534fb3776d32bd8e697006e91e4e2f7390c4591dd4d7d5a7cffd3f943. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/USJ3V1344624.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0c2e737fff64cff1f57175c5ed031912de50afcae0798cb2abef944a8f0e0401. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/USJ3V1344632.