thumb|Nik Bärtsch (2016) Nik Bärtsch (born 3 August 1971) is a Swiss pianist, composer, bandleader, record producerNastos, Michael G. Allmusic: Nik Bärtsch Biography , accessed May 25, 2018 and author
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 0x11b873fab0039659b5e93f587a937f1d5f210e0792df768131dafdc83cd8227e. 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/286e4533-aeb8-40c6-82e3-96ffb927d7d3.json and https://artists.proofprofile.net/proofs/artist/286e4533-aeb8-40c6-82e3-96ffb927d7d3.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 0xe550c06ce100847869e02104022c51b4b918cbdcc7afb785acf03bd2d4fac8ea. 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/CH7812191030.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbdef2a7d3bbfcf32985902b8f8119dcb14ab15adb562fecac8ae35d3339b3959. Chain 2 (Bitcoin): anchored in block 959008 (2026-07-21T13:14:05Z), 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/DEB330593902.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8c01c633ed803f711e2cb96ec5779f36e1610471e39715671597ae81ef1ce410. Chain 2 (Bitcoin): anchored in block 958935 (2026-07-20T22:08:19Z), 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/DEB330704902.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x22f0efeef8796c6b22e2549a3bea524d0cd31e865c3d6f3f00d3a6ad7853f693. Chain 2 (Bitcoin): anchored in block 958792 (2026-07-19T22:55:52Z), 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/DEB330704903.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x12df0f575b335f2bac2a4c5637cfeb9d68f187ae7ced9a7d76d6c6dc2bc1414a. Chain 2 (Bitcoin): anchored in block 959071 (2026-07-21T22:56:27Z), 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/DEB330704904.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8d472c6225f17f0c6fe0d77be0d80e3a3e9c366225cdf71b5acb4c3673816a9f. 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/DEB330704905.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8497159eb73bb8fac48afd0941061c68ec82cec90f65cbc5188a97ab0ea92337. 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/DEB330704906.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x329940056ff4f1384aaa91328f7117b651c2d183c620e10e6f2aeacddd98eb12. 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/DEB331017801.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5983a3f3e01b77778aceb985b7a8e3332716d09db84c86b0dd102088c03c76ad. 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/DEB331546403.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9feadb14e07687958d5991478184547e7ef663c641d7f3e5b3f63ea0cc45930f. Chain 2 (Bitcoin): anchored in block 959087 (2026-07-22T02:05:55Z), 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/DEB331546406.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x755b29503f8f610265769dacc0809e2090c29276b48e026636f50cc8bbdfd46f. 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/DEB331760301.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf6ebdec4d803871234dd5cc7df5c89151dccbc8cfc10a35ceb6588044765b913. Chain 2 (Bitcoin): anchored in block 958517 (2026-07-18T07:54:29Z), 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/DEB331760302.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfbbfe60a20fb5e7637542e3e174522cce52d68a46813d507395335ad898ca371. Chain 2 (Bitcoin): anchored in block 959084 (2026-07-22T00:50:00Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEB331760304.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7681ae31e4df561f3fb84bcf2fd780eddadaea0e4f06d972664412904631ea4d. 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/DEB331760305.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x99593d004b137513cbda58be30d51814154801b27b5158f14a6643b1eec58f8f. 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/DEB332070301.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb6d44821cccdfe2da8595e8090742e4ea57246552f139e04787674505ba9f488. 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/CH5142400273.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x50cefeccf799a2d704a31808f542da87e6499323223ae8ba3a27c331aecc57f3. 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/CH5142400274.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfbc34148d8ac2e972d61a618a95c0a2d61bff5c00d0b3c2883173e2236392217. Chain 2 (Bitcoin): anchored in block 958340 (2026-07-17T00:53:26Z), 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/CH5142400275.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x19962af4948837af65d62cde33feb8932a6f34f80e8a73f00707c8d98563ddef. Chain 2 (Bitcoin): anchored in block 958436 (2026-07-17T16:42:22Z), 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/CH5142400276.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2d17e7eacb795e4c75c4fd5ac70e1d8f87f2769302b557cc88e8210ffc789b91. Chain 2 (Bitcoin): anchored in block 958793 (2026-07-19T22:59:45Z), 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/CH5142400277.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc32220ea62b3807ee81e25bf28f5f5aa11ed41ef5213db6ecc5a7f83c7e65f56. Chain 2 (Bitcoin): anchored in block 960209 (2026-07-30T05:15:54Z), 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/DEB330725004.