thumb|upright=0.7|Duo Ruut performing with Jaan Jaago, Tõnu Tubli & Mati Tubli at (an Estonian traditional music festival) in 2023 (English: Duo Square) are an Estonian, contemporary-folk duo formed
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 0x8635592ba79aaf6ada798296300446cd748997d20264a1f28b5a4cb96f3995f4. 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/da561e33-bb81-4183-a8e3-a591c7ffe7e4.json and https://artists.proofprofile.net/proofs/artist/da561e33-bb81-4183-a8e3-a591c7ffe7e4.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 0x0c757c5ce6a7edc153d48b6befb8dd5015c93f4eea1771f3b5a1f86be4893ecc. Chain 2 (Bitcoin): anchored in block 958420 (2026-07-17T13:33:01Z), 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/EEBR31900022.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0de7e570126a4a4b9f878d7ecf5dbac369214798f77ebb8c2a745d098fb56a48. 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/EEBR31900029.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7503f3312eb18b4d448980918c9eeba528023cda690756255db4edd700545bc4. 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/EEBR31900027.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8f407a3ee64a3623175c05a14c6aa0895d65d34f4147f40575251fa70b9b8b3b. 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/EEBR31900026.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8c2107ecee75804ca05f003f55a94ac209b925ecf9e6a51f3c82293fccf6e2d2. Chain 2 (Bitcoin): anchored in block 958670 (2026-07-19T05:26:23Z), 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/EEBR31900023.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0cd28c276af340ce788f3d55b562a9bea6238a93d553f87904cc35efb78374d7. Chain 2 (Bitcoin): anchored in block 958697 (2026-07-19T07:58:24Z), 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/EEBR31900025.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x25c735f37c3f6e487f1bb75c164b0ab9538b6a23603c4642dcdc8c2f82021868. Chain 2 (Bitcoin): anchored in block 958263 (2026-07-16T08:19:47Z), 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/EEBR31900021.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x255e365aa36de1fe0e133908bfb6bfcb43ad70e6c92d5031f90653d3aec6b1d5. Chain 2 (Bitcoin): anchored in block 958245 (2026-07-16T05:50:22Z), 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/QZES62115817.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x87adb3b05811e70ef296ed3870ffbf2d6387fca67c291c2e7af3cfc22be7c333. 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/EEBR32100022.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x87adb3b05811e70ef296ed3870ffbf2d6387fca67c291c2e7af3cfc22be7c333. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/EEBR32100022.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5c829f38c59ec67ceae8a6a9ce9df407115e8d289457caa6addbe0db16391f6c. Chain 2 (Bitcoin): anchored in block 958697 (2026-07-19T07:58:24Z), 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/EEBR32100023.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfdc1e89f6502609133da671491c17fd609a000f0fbe8240017d68a44b97af714. Chain 2 (Bitcoin): anchored in block 958340 (2026-07-17T02:52:11Z), 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/EEBR32100024.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x07a2e61846a6f95f3c4aea0773f8330b51cb397aafaf96cc2490d89b77d466f0. Chain 2 (Bitcoin): anchored in block 958541 (2026-07-18T11:37:54Z), 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/EEBR32100025.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf255209663623128d9395349a925ec75fb11b63361fffea28dca4de545c74fe7. Chain 2 (Bitcoin): anchored in block 958601 (2026-07-18T19:27:02Z), 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/QZPLS2218400.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3992b08d2c8c5ca7cc7c4f2e41c8fea42e340c44bd61b3823848f9e75a5f197d. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/EETI12100003.
Tuule sõnad (feat. Duo Ruut) - Extended Remix
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb118c417e68ef10fbca8e3aa425d9fc0bd93c85aa38d172b74f1cce5c90ad160. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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/EETI12100007.