thumb|Slater working on a roof thumb|Cutting a slate with a slater's hammer on a slater's stake thumb|A slate roof A slater, or slate mason, is a tradesperson who covers buildings with slate. Tools
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 0x0577be3167ec0d7ce8393ee9a0ed3eefe626a6c63be396842840451b317ba3ae. 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/18eb8ffd-dc0b-414a-b388-11aa7c6d62a3.json and https://artists.proofprofile.net/proofs/artist/18eb8ffd-dc0b-414a-b388-11aa7c6d62a3.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 0x56ff86255ba7c893f3c1c06ea492d938b0f38c428bdd5cb7ed1bc2ff7f9953b1. 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/CAENV1946621.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd6d4e0edab859933625d4559d4bf43217191b523d44980c7a531d3bbba8d98bf. 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/USRC12203868.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe5a8eb22d43126addf5a485b8e2343acacdfe289c478816394e0c42904e1666e. Chain 2 (Bitcoin): anchored in block 953536 (2026-06-13T17:25:41Z), 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/USJI12100071.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x47c197f746b8439ed2c97fcf51e13de4145e5260036874f491c7a437261cb4ea. Chain 2 (Bitcoin): anchored in block 953513 (2026-06-13T12:47:07Z), 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/USRC12203869.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb8f73ecd4cfebab70b3a4673814e966dd5fe763e713918d5d8815e10195ef493. Chain 2 (Bitcoin): anchored in block 960225 (2026-07-30T08:04:30Z), 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/USRC12203716.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x47c197f746b8439ed2c97fcf51e13de4145e5260036874f491c7a437261cb4ea. Chain 2 (Bitcoin): anchored in block 953515 (2026-06-13T12:53:06Z), 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/USRC12203869.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd6d4e0edab859933625d4559d4bf43217191b523d44980c7a531d3bbba8d98bf. Chain 2 (Bitcoin): anchored in block 953515 (2026-06-13T12:53:06Z), 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/USRC12203868.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3392102b037a747ceec6fc17c23dab1688cc8c90cd7bf23cd198911b87f596fe. Chain 2 (Bitcoin): anchored in block 960266 (2026-07-30T14:44:50Z), 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/USSM12210694.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x75efe6d785adbe6e1cbee0731dbfe358713e05eca8fcddeb4a5e4dded9f811be. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/USSM12109759.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3fd62e240a8d8ac31c00720e70777251706581b6106b64450425b28355f3fd55. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/USSM12106073.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbe645052a099cb8adbb16ef2a94646e77aa3187c79a8fe733bcf78cb5e5a6c87. 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/USSM12208182.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3fd62e240a8d8ac31c00720e70777251706581b6106b64450425b28355f3fd55. 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/USSM12106073.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3fd62e240a8d8ac31c00720e70777251706581b6106b64450425b28355f3fd55. 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/USSM12106073.