thumb|From left to right: Sammy Marks, Barnet Lewis and Isaac Lewis Isaac Lewis (1849–1927) was a Russian-born South African industrialist. He was the cousin and partner of Sammy Marks. He arrived in
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 0x5d464f7a1581a8329f425f5dc6e3aeff1d604d0d89a2005603856b4d4614aaaf. 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/5e400161-bacb-464f-96ea-8cbfef647cf6.json and https://artists.proofprofile.net/proofs/artist/5e400161-bacb-464f-96ea-8cbfef647cf6.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 0x90ac1a7db6dee7e81fc41d7c9bba0df80a306414c9b7308f3a794f15bc1a1aec. Chain 2 (Bitcoin): anchored in block 958410 (2026-07-17T12:18:07Z), 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/TCADE1715122.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x786f65a2d46dd3e7c84523443f5dad2f1782ab20fbb82098a3dc71484e65deb3. Chain 2 (Bitcoin): anchored in block 958079 (2026-07-15T00:21:05Z), 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/TCADQ1832974.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x62cd2121b45dfb5acd4d96d47b2135e02b999e3a1550ab743e03b8987d616729. 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/QZDA81892051.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7539c35c75733e830d4317d763fae58e87066d73c0217e3462d1b342b9151430. Chain 2 (Bitcoin): anchored in block 958194 (2026-07-15T20:32:27Z), 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/QZDA81813784.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd9b15b3d8b87aab018e44e3799ffad6c3e08bd358d76e78332ff92663aeab52f. Chain 2 (Bitcoin): anchored in block 958455 (2026-07-17T21:28:36Z), 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/QMEZE1949334.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd9b15b3d8b87aab018e44e3799ffad6c3e08bd358d76e78332ff92663aeab52f. Chain 2 (Bitcoin): anchored in block 958166 (2026-07-15T15:55:19Z), 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/QMEZE1949334.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9641019195097e993564aee97ffd46cf4111f73045a75baa6eed01de6c3d9e17. Chain 2 (Bitcoin): anchored in block 957754 (2026-07-12T21:26:22Z), 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/QMEZE1949165.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa725fb28f13c3566d6a96b5a4bf0bd527385515017876fc5c6e96ba700a61d28. Chain 2 (Bitcoin): anchored in block 958607 (2026-07-18T21:01:11Z), 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/QZN882211936.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f8230bc54ba0a46c9fdf5501a1136bb73f1290d816da8f014b5d2c5b3e49bc7. Chain 2 (Bitcoin): anchored in block 956402 (2026-07-02T22:05:07Z), 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/QZN882243257.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd139bb68dee151ca5c9461717348509d708fbe7f2aa6e4001169f0e3b8663975. 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/UKXN22557558.