thumb|250px|Men wearing kanzus at a wedding in Kampala, Uganda. A kanzu is a white or cream coloured robe worn by men in the African Great Lakes region. It is referred to as a tunic in English, and as
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3e4182e35f9a45ffabb88c65d9a6f23753543f94279a4fb3e06822e1780ac8f7. Chain 2 (Bitcoin): anchored in block 953654 (2026-06-14T16:26:51Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/48ecddb0-b040-41b7-9f0b-0bdf33b96588.json and https://artists.proofprofile.net/proofs/artist/48ecddb0-b040-41b7-9f0b-0bdf33b96588.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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x91cc49e26a8861d578ebb88cefa077b506e9fb0fe0d00b9426b1a3c92e7bae22. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/QZK6H2125193.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x32f27546f4632eea72b2c8da46f1e200585f897483366ffb03c8f7969cb228ad. 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/QZK6H2125195.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x120362dcb8f76bed508228b476a2c31a7b6f97f89e2853bc52ae174c539c1f8b. 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/QZK6H2125200.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x99e3b531d13d8b5aea26e447d50f09c4962ea84fd28aadd81544edf6eec7c502. Chain 2 (Bitcoin): anchored in block 960513 (2026-08-01T04:52:22Z), 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/QZK6H2125197.
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 0x876a7e459c120bb4522c5e83286397c7904eb85972533c03f106c9745bd06e88. 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/QZFYY2232150.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x60633a83df7477678e164ccf7b366cfa5bd01a0409415ccbd2587a424763c9b7. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/QZWFE2381453.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xad87bdecadee6e1cad02c543b55856b97eb00df1176b98e9dd353b81cb9069ef. Chain 2 (Bitcoin): anchored in block 960334 (2026-07-31T02:19:15Z), 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/QZRP52296302.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5e5d30cd32a983da81b3291f039165e5987b360e938800409891dfd693cb0ae1. Chain 2 (Bitcoin): anchored in block 960427 (2026-07-31T15:59:18Z), 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/QZWFE2381455.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x13848fb6ae778a929623df98147525ca89c4ed68d62de5822beee2a89338b6bf. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/QZNWX2474461.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb488a530760b36beaaf7641af87abe1b99b4400e431c04e99ac2063df2837083. Chain 2 (Bitcoin): anchored in block 960427 (2026-07-31T15:59:18Z), 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/QZNWX2474460.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x39f784034a9d6b8c23151f4f71eb28ff9ec172d7ccf28a77a880e171f5199678. 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/QZZ7R2482947.