The Opposites are a Dutch rap group, consisting of Willem de Bruin (Willy) and Twan van Steenhoven (Big2). The two started rapping when de Bruin had to write a rap for his teacher as a punishment. Wil
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 0x6b1d593862435676100d80d49d303bdd964d52c91f9d1fefcedb3fe1aed89168. 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/c238e9d1-579d-4da6-bfd4-9aebb77da839.json and https://artists.proofprofile.net/proofs/artist/c238e9d1-579d-4da6-bfd4-9aebb77da839.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 0x1074fed5d44c8b0551ebd22ed739b66cf01285c468bf5ed1678fd5f8690bf323. 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/NLG661300257.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3c52abf9b4528530f481ba855e45952921f02f2f04471ea29b2c0ab9b0eae683. 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/NLG661100458.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xda5339c9d2dc3b92ef881db1232b8483ec9f6587345be2ec8f31cf7ca903ccf2. Chain 2 (Bitcoin): anchored in block 960344 (2026-07-31T04:14:58Z), 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/NLG660900057.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8e1340ce0ce5685886cdf94faec00e090ec4a6ca849ae65431dc40056a575dd2. 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/NLG660800115.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x62ac05a324886806137117c7849f424e49b12e8ffac1dfb7848af356947efec1. 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/NLG660900059.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd3d039c9441478054f627a7e901a1a06683134dd9a0982e4d661ef396292cddc. 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/NLC340801006.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd3d039c9441478054f627a7e901a1a06683134dd9a0982e4d661ef396292cddc. 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/NLC340801006.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbf63de9f3d889683179131a40a1a44121d56ddee5cd99b2e06358368d39382af. 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/NLG661300341.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x74646714fa1a7565f6b57a1cc058bc1059ed92fad812bf8fe37cf7be79ec6f3a. Chain 2 (Bitcoin): anchored in block 960284 (2026-07-30T17:23:26Z), 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/GBKQU1783831.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd91d67406b83f67bf83eab45572c0cbd2a4c4c25ddc9ecc59456ac6e43fddf4f. 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/NLUM70600644.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbe0ea2f9be1495246b7e5c2a7302b35158b7f75aab756f9b1c45da9310fd43b7. 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/NLUM70600656.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5b404b798b017e64f9928568cbca116040c0ed89a042016cc52619e25a8b1abb. 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/NLG661300247.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x13b7a0f44149b64ed1855b65cc2f53191e039be56f7edaa242840607921bf974. 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/NLG661200323.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4f3172c4fc3620583b5cd7e210ed7b7d550ab06f1c14a4071c002f66ece296b2. 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/NLG661300175.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x346d9fc3382500cc7ca4ea06ee0412291e5b2108ec44424d5c851e95049ec054. 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/NLG661200411.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbaa4094d45c854c50ebb5d13c1d65af4de5e6448b4da20ba362e9534966f8b35. 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/NLG661200332.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x319e7a278c65e5e0f328790f31b3cd65c043572bec43844e9055a36d57837e31. 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/NLG661300172.