Single file may refer to: The Single File, a 1983 video compilation and 1984 box-set album by English singer-songwriter Kate Bush "Single File", a song from the 1995 album Elliott Smith by American
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 0xbac90e92834d0279d003617cbcfc4e48ba2931e2921d418dceee2e5cc05f3ea0. 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/8c9933e5-a2a8-41d6-9b4d-1b8c0737cc32.json and https://artists.proofprofile.net/proofs/artist/8c9933e5-a2a8-41d6-9b4d-1b8c0737cc32.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 0x1e23b5b9d8cfe489db65f8545371effc2cca03cf094c1c5743690a4b8602df2f. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/USRE10801407.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d567820029f8dbccaefbb0f13a484498f8c7dd095a0642b3dfea937fca5e02a. 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/USRE10900265.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d97279b0fdc208d54bc2f8ccd98eaafeb6260cfaafab87b3574855ecc537a8d. 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/USRE10900266.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7d40b308576c33370c701c72870119e00536a9459a6727491cde2fd94f6d6d0c. 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/USRE10900267.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd9f50e74d57c0be9926b373be6b688a96654d88728cbdccfb11424fc1674888a. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/USRE10900268.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x857f3600fd46d30857513eadd4e4c799e9e73d204f10bc9b20daa980edf46e1b. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/USRE10900269.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x97c90607992cd76e095d4abe590f625b2697c546f2c6cbd9d8343b68b7a05099. 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/USRE10700744.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8c25e5b9d9f97ce4ccac50be75f69f2fd11234293818064ebfae34b95b5d5137. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/USRE10900270.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc64a891c4ee4aefd124dbed061703414e9b6af93e81b8c6462210db38ed110ee. 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/USRE10700722.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdccb749a0b1527dfc0a12d63f5a7be923843a568445f38135db4856d58171818. 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/USRE10900271.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xef00d18b297b8a2522715a8f7872b35cbff65086d79eed72523784324d3f8727. 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/USRE10900272.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc64a891c4ee4aefd124dbed061703414e9b6af93e81b8c6462210db38ed110ee. 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/USRE10700722.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0c5f8b424b5d82f4cc1ee5465e346914015dc323308f90fb9dedf89ff89f355c. Chain 2 (Bitcoin): anchored in block 957067 (2026-07-07T16:54:37Z), 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/USRE10700743.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x97c90607992cd76e095d4abe590f625b2697c546f2c6cbd9d8343b68b7a05099. 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/USRE10700744.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd09713344d80a70010795a5975599ebb3e83f7dfdf53e9cbd161db88c23595cd. 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/USRE10700745.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd8a9e5041d41ac5b8b0bb3223a010bdc02a641391b9792fb4f55a4de5c265faa. 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/USRE10700960.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d97279b0fdc208d54bc2f8ccd98eaafeb6260cfaafab87b3574855ecc537a8d. 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/USRE10900266.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1e23b5b9d8cfe489db65f8545371effc2cca03cf094c1c5743690a4b8602df2f. 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/USRE10801407.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc64a891c4ee4aefd124dbed061703414e9b6af93e81b8c6462210db38ed110ee. Chain 2 (Bitcoin): anchored in block 957046 (2026-07-07T14:04:01Z), 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/USRE10700722.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0c5f8b424b5d82f4cc1ee5465e346914015dc323308f90fb9dedf89ff89f355c. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/USRE10700743.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd09713344d80a70010795a5975599ebb3e83f7dfdf53e9cbd161db88c23595cd. Chain 2 (Bitcoin): anchored in block 957061 (2026-07-07T16:07:00Z), 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/USRE10700745.