thumb|Arthur Rubinstein in 1937, by Carl Van Vechten Arthur Rubinstein KBE OMRI (; 28 January 1887 – 20 December 1982) was a Polish and American pianist."Artur Rubinstein", Encyclopædia Britannica Wid
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 0x1a10f4d3d0148eb0a63e445e180445a9bb092d8902f819678175bfb2a9142e39. 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/739fc30c-48d5-4c16-91b2-d833baf0739f.json and https://artists.proofprofile.net/proofs/artist/739fc30c-48d5-4c16-91b2-d833baf0739f.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 0xab1ffc9af7a23ed4cbbc4e7f49bb01592b6559449daabfa9e6e0bd9b3bc6f01a. 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/GBAYC9200814.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4e0096710b78bc8981cce3f84c4f63dbd43666cebd65ddc3f1923b3fa5a1d53f. 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/GBAYC9200815.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5fdd4845d26405b9b86629b9c5743c5e6c7ab352938f8f753d9b8edf248ade73. 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/GBAYC9200816.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4d39fec100ca904257aac5de22803d9cf6bf4b627ddcaa4c3f0f31239479fc24. 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/GBAYC9200817.
Nocturnes, Op. 15: No. 2 in F-Sharp Major
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5bbc6331408198547536f432eae197ddd9c9dddcaea8f71d8692617567be49cd. 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/GBAYC9200818.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x151bc12b85a3d0a889d944412a2f223e1c4b6722f56ba6e63877f8b980126b59. 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/GBAYC9200819.
Nocturnes, Op. 27: No. 1 in C-Sharp Minor
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x28a7420d016e153e2a187579710de2c008f434d2a2bf02a98d0ac73de402f8f2. 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/GBAYC9200820.
Nocturnes, Op. 27: No. 2 in D-Flat Major
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc79ea4614f79c37f9f0623dfddadfca99fcfd3a0f295030ac30cc03e08c4ce35. Chain 2 (Bitcoin): anchored in block 960138 (2026-07-29T19:35:34Z), 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/GBAYC9200821.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa89609df4e8f4f015a633c0484c909033ab9467d8816e26bef94515e59200c43. Chain 2 (Bitcoin): anchored in block 959128 (2026-07-22T12:33:25Z), 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/GBAYC9200822.
Nocturnes, Op. 32: No. 2 in A-Flat Major
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1b9bacb65b628089cda2a24ac98c099ac85dd120535ffa7c783a63ef95c15fc9. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), 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/GBAYC9200823.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb521faecf500db68b26c184de90d098c6ca09c7e315848f7647aca6f8ed05e47. Chain 2 (Bitcoin): anchored in block 960138 (2026-07-29T19:35:34Z), 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/GBAYC9200824.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4dbeab3c69cd91682149226b019d6c1e4adb660f0279d6b53b4e89b49a1d042f. Chain 2 (Bitcoin): anchored in block 960105 (2026-07-29T12:35:17Z), 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/GBAYC9200825.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc40e732c5d3484f519a4761e9c8292652e09db30bb8233ab374752051d201ab7. Chain 2 (Bitcoin): anchored in block 960138 (2026-07-29T19:35:34Z), 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/GBAYC9200826.
Nocturnes, Op. 48: No. 2 in F-Sharp Minor
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfb8d1843f0c3e2ce6da6afa616cb2cb96ac082be0b2f99a71203dfd147e43ea6. Chain 2 (Bitcoin): anchored in block 960138 (2026-07-29T19:35:34Z), 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/GBAYC9200827.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x534342fd976276317e5973a6f22a3b7c6a04b4ac19bcb1ebc9bb5568fc28af83. Chain 2 (Bitcoin): anchored in block 959159 (2026-07-22T17:48:40Z), 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/GBAYC9200828.
Nocturnes, Op. 55: No. 2 in E-Flat Major
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd40c424e27d058b3d1ff2fcab4e29d68f466a8940e0b715a18e784882e9893a3. Chain 2 (Bitcoin): anchored in block 960125 (2026-07-29T15:38:18Z), 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/GBAYC9200829.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x57bb368f07a95a0300004e9389edfe7d9cadea60c493eae6168dd861eb1990e5. Chain 2 (Bitcoin): anchored in block 960117 (2026-07-29T14:28:24Z), 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/GBAYC9200830.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe496eb2dd71d14f25b0747fd8e8653793eefd8a5536a3d6276ce7d3913241474. Chain 2 (Bitcoin): anchored in block 960108 (2026-07-29T13:09:35Z), 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/GBAYC0500205.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3bbffdfe1904dacb15118adad5256f762f137ed6d49437aa552b16c2fdfc58b5. Chain 2 (Bitcoin): anchored in block 960099 (2026-07-29T11:30:20Z), 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/GBAYC9200832.
Nocturne in C-Sharp Minor, B. 49: Lento con gran espressione
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9875746026fcc8250ba9d27b5a2135351f93a3431f68fff386145985249bee60. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), 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/GBAYC9101707.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe31b5909fe65bdb80231fa278830b925e587b1d95b0a7b2fefe9fabd2ca1ad1e. 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/GBAYC9101708.
Piano Concerto No. 1 in E Minor, Op. 11: Allegro maestoso
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x91603d385f4d0cfbe3cc757528d69157e248eae1762f371d331b3b856db347e0. Chain 2 (Bitcoin): anchored in block 957073 (2026-07-07T18:39:05Z), 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/USBC10500554.
Piano Concerto No. 1 in E Minor, Op. 11: Romance
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1e4aaf95a7e33b7b840bb47a236b9030baa6d189f94e84bcceb8cb20c677eb35. 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/USBC10500555.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc556f878d81400fb01e8835f73696d8d4de3ccb7ca8a16c2d54937db1d758a32. Chain 2 (Bitcoin): anchored in block 960144 (2026-07-29T21:09:47Z), 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/USBC19802926.
Piano Sonata No. 8 in C Minor, Op. 13 "Pathétique": II. Adagio cantabile
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5d1f0d1be3bd1d336fb381486d22f1145f68fd69e7dd0dcf2c45417db888413f. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), 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/USBC10100662.