Kaliber 44 is one of the biggest Polish hip hop groups, formed in 1993 in Katowice. The group is dubbed the most influential Polish hip hop band, while their so-called hardcore psycho rap style is the
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 0x1d1112a646f700f52c8d8f4555329e032586284e6e00122db51bc2f6e17bd711. Chain 2 (Bitcoin): anchored in block 953423 (2026-06-12T21:20:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/db5551a2-7b82-47f9-9e6e-8731852042f7.json and https://artists.proofprofile.net/proofs/artist/db5551a2-7b82-47f9-9e6e-8731852042f7.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 0x23af2a6734e7bfd48b0851eb4addf26145ded18e0934e50ef07302bb13c7841e. 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/PLE781300161.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc040ec660e026228a8044edef2d55f61886a43178c44e401d19201ec3528c229. 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/PLE781300165.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6ac7269f1df11ad8982473ded868dc5366ef9f9338a233fb04c12f31cb37afed. Chain 2 (Bitcoin): anchored in block 956551 (2026-07-03T21:18:05Z), 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/PLD961600001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x497597079f7a6f4ca1cf3ed111d501c230c5d3c9c8d88aa70a40a4c1d0865bd1. Chain 2 (Bitcoin): anchored in block 957892 (2026-07-13T18:21:16Z), 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/PLD961600009.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbf85c1d83cc11d3c15aaac89d713a91fafaa7a781024efc451255d76692b1cdb. 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/PLD961600011.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3342515014bda6f3eab37293dfa0195f43b65f1ee281d012c3bd99ff4a47038b. Chain 2 (Bitcoin): anchored in block 956500 (2026-07-03T13:55:21Z), 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/PLD961600013.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x67bf073d0ded225930f45e7c0ea45defc25b3d3fbddc8151332e3d3bf7e73556. Chain 2 (Bitcoin): anchored in block 956576 (2026-07-04T02:06:47Z), 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/PLD961600014.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2d41a2b8db005a35767ceb7baae375e8a7fc1a0afb2e32468eb0f1216daae12e. Chain 2 (Bitcoin): anchored in block 958137 (2026-07-15T12:19:52Z), 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/PLD961600016.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1142d6352892c251e6d452cda6095c960360a815e7205d140532c085bfa0bbca. Chain 2 (Bitcoin): anchored in block 958444 (2026-07-17T19:12:23Z), 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/PLD961600017.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xeb9cd698a4639f1727d5bb59ffc9268f0fac978c46d792b41bea7edfe70342ea. 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/PLD962300001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x99498c5e4865d805c2b06fd55cc58029b01599ac5471b0fcec32c1a1e2e0ed0b. 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/PLD962400000.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb7b126d9615b6febcb29ba8f01ea046c0dd9d23f8f3777eb99b8148cb77df1b6. 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/PLL371400101.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc8db9a628b57011c2144b718c70ca99e1d48d1d8ac9cbdec0d8989ab8a0d2775. 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/PLH441700085.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0510e052ef11031afa571d41b19f33a6cb427d89b34c62342263256ed20df479. 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/PLD111500007.