2 Brothers on the 4th Floor is a Dutch musical group created in 1990 by brothers Martin and Bobby Boer. The group has had success in many countries including the Netherlands, Belgium, Germany, Greece,
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcbe25ddbf5493770ee8362491a541f8161dcb255243778e7655bb07048ba70c6. 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/fd34e173-2dd3-4562-af73-c9fd4b8d6448.json and https://artists.proofprofile.net/proofs/artist/fd34e173-2dd3-4562-af73-c9fd4b8d6448.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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7ed70bab42902d931e22b46d16111bcc9d8cef275801f6c709f9c91d988ba4e3. 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/NLA240305445.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa303eee8440876682bc86eb811726e5ed9ce01216ab44d0862a9a6b71f91a8d5. 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/NLA240305444.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1fdc6ef998ab3a3506f865dcd68fb2e8a8babbe3922b57d51516487ab6b2788d. 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/NLA240305441.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9e31e9a38f4f952707f90a5b9c027f71cdaf15a6a28a65f7b97a93d50af182d9. 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/NLA240303006.
The Very Best of 2 Brothers on the 4th Floor (25th Anniversary Edition)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdb62f0efc0994f2ce9427eb4aba8e8ffcf8e7166fe48d200339f4bb936eb997e. 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/NLA240305451.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6f40001a7129a8ce97557df38d1ff1aba84d11b531328e0e699d3f49b51f9f67. 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/NLA249800171.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f2d0cf92619f507fc0ed616b95d0948a0b7b4fe48d908f06c6f7f2adb8b401f. 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/NLA249900222.
Dreams (Will Come Alive) - Extended Version
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8fff89202fc88255c891b178481cf9d24052d33a1ef785e0d3e938acaead7894. 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/NLA240305073.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x295af7848a7ec3c41bfeb131b2f18c971ebbeedb11c6d6afdd70b89f8346afe4. 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/NLA242101042.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa8efde0a51d565d4f773f1b5970eefbabca3bccc134e3dec14adeb13581c67a1. 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/NLA242101036.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0f4c6e28198b92b1bad9c7ccc1998c72f7924dea81d9ea2cc57994fac537c484. 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/NLA242100781.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x952d8e670cde9aec3bd2f2882228a00d6b25ea9eb4f0518b2b93f141109e69a4. 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/NLH2L2200364.
Come Take My Hand (Twisted Mindz & Anklebreaker Remix)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf173238b3164fa2cf5980f613ca92f6e8f01c1bcfe927cb8b17b42f82f8b1be9. 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/NLA242100656.
Come Take My Hand (DJ Norman x Billy the Kit x Housewerk 2019 Remix)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc2fadeaa61e64e2ebeec14e4112c806bdf1e049cbc2b7fedd7472663e13c9505. 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/NLH2L1800239.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f2d0cf92619f507fc0ed616b95d0948a0b7b4fe48d908f06c6f7f2adb8b401f. 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/NLA249900222.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6f40001a7129a8ce97557df38d1ff1aba84d11b531328e0e699d3f49b51f9f67. 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/NLA249800171.
Fly - Through The Starry Night (The Remixes)
Turn Da Music Up (The Ultimate Rave Mixes)