Piotr Cugowski (born 5 October 1979) is a Polish musician. He is the vocalist of the Bracia Group, which he founded together with his brother Wojciech. He comes from a musical family, being the son of
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 0x9f2d3747a1ff70d573fb54054d6914725b4d249de553e525877760e537bda849. 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/39138887-4c5b-4473-8eed-4a8db6b447f2.json and https://artists.proofprofile.net/proofs/artist/39138887-4c5b-4473-8eed-4a8db6b447f2.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 0x9c741438271208facb23f2f1224e2b5ff0ce87eec4974bf7538b6b04984c6291. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), 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/PLA961800350.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1f781284f52e78dca87651842b5bf9cb843c2aefdc11f2e452f9b24ed8e8a1ff. Chain 2 (Bitcoin): anchored in block 958785 (2026-07-19T21:40:06Z), 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/PLA961900372.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4f2e5da3c114e93e736c05c81c6dffc95b0146252226f18e12fcf41f83d08bfb. Chain 2 (Bitcoin): anchored in block 958878 (2026-07-20T12:32:15Z), 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/PLA961900367.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5288e20c2aa8e7b9ef57dcc6718d79afeb2596878787221eefae83ae39b24a81. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), 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/PLA961900369.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc545e99f883b5994f3189ccc181440829db0a7596a8fd71efea20a5f309befd6. Chain 2 (Bitcoin): anchored in block 958876 (2026-07-20T12:15:48Z), 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/PLA961900371.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4adbf44de55094ae14550c83c8056d083ec75d5a2566cc446a8aa7a458e0ae2f. Chain 2 (Bitcoin): anchored in block 956772 (2026-07-05T10:01:46Z), 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/PLA961900374.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc49a9ba80e4e9a2e717a814666a98e834506ee2c51a9e559e52546db2474f640. 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/PLA962300472.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf1321f6b10dced2ebf2e688e06d52875184902c36cfbf5280801e94845a06057. 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/PLA961300174.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xed07271ab2b32d3a5ce1a1d1269a2f2bfa4a679bd18744254ebdfd580cb36813. Chain 2 (Bitcoin): anchored in block 959152 (2026-07-22T16:23:52Z), 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/PLA391819204.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcfda764fab388fb7736c0ea4f26171156abdf2836bea74efc3a60f1e8580e3be. 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/FRX762373920.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x96d92467f21853bd8e2e43042deb3a4fdd6b1b6d3e311bfb01e5e96b42d46aa5. 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/FRX762373937.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0190197be5bb319ca3791274370005352a29b01d05eadea335bec5bffc0b6a19. 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/PLC281200013.
Grzegorz Ciechowski - Spotkanie z Legendą
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc8547891c3595cdb8244fb6bc3674c0c683db8182c969db462bf1801b934b9c7. 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/PLA391593201.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1b29e91ce8cd50264a8f47b8add6f0f60d9fb8cb7d8206493ea972fd23817ac8. 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/PLD272000006.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xabece8e70f80a7ecbfc19c496dd5c200f6c864b153fec5c33530c4baaa6cfee6. 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/PLD272000015.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcb316751429af65cdec9d813eceb273a169ef83508e884e394868a3f7e6e35e6. 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/PLA812000023.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9118164963fe120fbce5e90943c7d933396d654a67f2b65b3944715afa944f19. 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/TCADK1710258.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf74a2ae44ad8c4ffb4dc173ea2d5909b204e6a9e40c70e6b190d98e391698731. Chain 2 (Bitcoin): anchored in block 960160 (2026-07-29T22:48:59Z), 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/TCADK1710264.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x78f9163436a036007ecadceeb0acad816e704c227bd4ea75080d91f0c2339307. 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/TCADK1710270.