thumb|AI-upscaled image of Robert Natus Robert Natus (16 March 1890 – 31 March 1950) was an Estonian architect of Baltic German descent. Born in Viljandi, Estonia, Natus studied in Tallinn, and at Ri
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 0xc3c16ec7a7525e7d3f0091dc39f93dcf4013bf233dc6f397759f0e3de70ffe8d. Chain 2 (Bitcoin): anchored in block 953741 (2026-06-15T04:44:49Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/9c3e7d72-a718-47f4-8ac3-ff1327df8b55.json and https://artists.proofprofile.net/proofs/artist/9c3e7d72-a718-47f4-8ac3-ff1327df8b55.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 0x44d965cd5e1124e3533c31f598a86ccf5434dd1cd63c5d2fc61f630618b96eec. 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/DEH740400373.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x233c04342bc254ad457bbe4e9382afeb348244492e0f77b0ce1da58dea3a837a. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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/DEP780400232.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x13b389463c28b594a3914b55cbdbf26858c264f80d1239ac408430da953f4350. Chain 2 (Bitcoin): anchored in block 958286 (2026-07-16T12:43:37Z), 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/DEG840500850.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x31847faa705ff0e47c7ba79220415fd742858fed067290c369999e3ced91f5dd. 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/DEG840500900.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x536ab5cec20b0d523a0fcc970b89140e232596d1f6eebda49f06a903703e981c. Chain 2 (Bitcoin): anchored in block 956826 (2026-07-05T19:27:56Z), 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/DEH741003304.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9857d34ec34135142fa09d4814fe8ea46364e95df9ac18fc9c4cf9a2bdbe7489. Chain 2 (Bitcoin): anchored in block 958891 (2026-07-20T15:56:26Z), 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/NLCK41065247.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x16319ba780212036c29d32a83f0263cbe5514e5ba2c15104a17e98761b94744f. Chain 2 (Bitcoin): anchored in block 956375 (2026-07-02T16:51:38Z), 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/NLCK41065249.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd8094908f34af05d4fb08587ff1389a6713f0dbbda5feca3097829a10139d0fb. Chain 2 (Bitcoin): anchored in block 959011 (2026-07-21T16:22:15Z), 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/DEEZ12200445.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xce2e1179e8bef1d8cbdd2f86357b5ee052c2e24a1cf5bf17805a192646a3f439. Chain 2 (Bitcoin): anchored in block 958853 (2026-07-20T11:33:33Z), 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/DEEZ12400536.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x73568cc6efbb2d3ecbd940f85c1a83a17e64b99fd38b785d98048dba76371edf. Chain 2 (Bitcoin): anchored in block 958576 (2026-07-18T16:22:28Z), 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/DEEZ12400538.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x68e771deff000b6e8a73d78c91d26ee9497b08539c5521a94c71f8d29774f12e. Chain 2 (Bitcoin): anchored in block 958590 (2026-07-18T17:28:56Z), 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/DEEZ12400541.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x66bfded0085cd633ba3d0aaea1ddc1984b8eb10ffe330a9b38d7d2e310c43c6d. 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/DEEZ12400549.