Matija Cvek (born 9 March 1993) is a Croatian singer and songwriter. He rose to fame by participating in HRT's show A strana and as a backing vocalist during Jacques Houdek's Eurovision Song Contest
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 0x61a679f393ae7135a826e64a3eddf65a78244635ee24e9fb315229d53e753a41. 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/e91efa9d-bab1-45cc-b6a3-026a29b4c875.json and https://artists.proofprofile.net/proofs/artist/e91efa9d-bab1-45cc-b6a3-026a29b4c875.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 0xd2eb26705becfa8c635af3e7dcddb1776cadb85e36e3ebe20a97d8c0b391af5c. Chain 2 (Bitcoin): anchored in block 958194 (2026-07-15T20:32:27Z), 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/HRA111430801.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbb956fcd9a5337bae45c46ab794fee44cea722435dada3192783b7550fbefa4f. Chain 2 (Bitcoin): anchored in block 958286 (2026-07-16T12:43:37Z), 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/HRA0J1500016.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfe8aa3e5aa20a2e00180013d4b9f825e5e241c543849f0430a870b52197301f7. Chain 2 (Bitcoin): anchored in block 958461 (2026-07-17T23:18:11Z), 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/HRAA41900359.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4056a5b6c64b98e9c0f117b0f1cbad0ca0460da957e3d0c4e961ac38e576abf2. 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/HRAA42000023.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2230634558204edd8b01f909117a79aae2268cff3b48c2395bb4f9c8641a909d. Chain 2 (Bitcoin): anchored in block 959076 (2026-07-21T23:41:40Z), 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/HRAA42000113.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9a6d722837c69e63dec85f724360e15520523fb18ff10a3b1d26ccf60237f482. Chain 2 (Bitcoin): anchored in block 958091 (2026-07-15T03:17:03Z), 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/HRAA42100014.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xce9bac1d100b87dfcc13f71e36a272e80fc418442f9d515a9542f4135caea7ba. Chain 2 (Bitcoin): anchored in block 958176 (2026-07-15T17:14:36Z), 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/HRAA42000090.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb7770a67ac83331206be11e3c07a4e92f0872c62c7e2ace7854bc1ed0997b9fe. Chain 2 (Bitcoin): anchored in block 958268 (2026-07-16T08:56:51Z), 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/HRAA41900035.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd092d100ee98f7bdc6d1598a4327bd972951e9579ef28a58e2058e006a671313. Chain 2 (Bitcoin): anchored in block 958695 (2026-07-19T07:37:00Z), 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/HRAA42100037.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x44587450a537af616397d359223f47227c2ec5de4e9739081ee9d2325d42e5c8. Chain 2 (Bitcoin): anchored in block 956725 (2026-07-05T01:12:41Z), 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/HRAA42100038.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x872c0000c715304bf7f5e133e086446ce982394e5267dd516fd05282aa6bed12. 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/HRAA42200288.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb5eb0477aabae7fce915675e2f31a6dcc86417af5139219c93240010fd86ad10. Chain 2 (Bitcoin): anchored in block 956822 (2026-07-05T18:48:28Z), 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/HRAA42300129.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb3422097f11f4eaa3b821c48ad52f58d7b4f2b5c5e6d2a9ff3b0d1258062a676. 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/HRAA42300142.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x03655cb08a727a9e6c67c563f1b179c22971cdc4d6a027208e3ec4d595f418af. Chain 2 (Bitcoin): anchored in block 958796 (2026-07-20T00:01:46Z), 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/HRAA42300147.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4f8a9f96c85d97b47021c9146addbd82f99c4b9849907c701591db837ca191b5. Chain 2 (Bitcoin): anchored in block 958520 (2026-07-18T08:19:09Z), 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/HRAA42300149.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x62895fcd664ca91880a95b75d9370c7efc4d5349635ed2266dcd18796a063827. Chain 2 (Bitcoin): anchored in block 958800 (2026-07-20T00:52:19Z), 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/HRAA42300152.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x34b0cc0969ba6cdbbf81cd985b0132740a695ec9ff1b6f5e39657773f0089f97. Chain 2 (Bitcoin): anchored in block 958224 (2026-07-16T02:28:43Z), 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/HRAA42300226.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1ccaad878006c69dcbecd8ba6a80d9b7513cf7ce8e016cb44e8997c0fdb60639. Chain 2 (Bitcoin): anchored in block 958137 (2026-07-15T09:47:57Z), 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/HRAA42300227.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5382276f4acdbd8fdabb57e6cfbf25a5f33966ba7ee958b17014a662673a3cf6. Chain 2 (Bitcoin): anchored in block 956482 (2026-07-03T10:33:57Z), 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/HRAA42300230.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc1ee70beae522f70f8bf2bb4a27ff1f9b1fc5c95826bd5a18230ee685981dcfb. Chain 2 (Bitcoin): anchored in block 958980 (2026-07-21T07:04:12Z), 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/HRAA42300231.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdbdfbde71e949b52cf9102d976bd186405f0427809c91315ae358a2b6cb9e368. Chain 2 (Bitcoin): anchored in block 958639 (2026-07-19T01:18:30Z), 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/HRAA42300233.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa6d0454648e6cd25dce5318b4a33f52a338f99c8c61220f51a6f78808217a07a. 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/HRAA42300234.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc1e382fc0875e0033df04bbc6d0311842d6cacc0289c64cd2bda1a9ff4fe4f86. Chain 2 (Bitcoin): anchored in block 956482 (2026-07-03T10:33:57Z), 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/HRAA42400052.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1eaaddc3b1607e06cf353492b4d57e9de9a77f73bb6367bf3ce7e67798e4e599. 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/HRAA42500214.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf216b9dd4350789f64e10220e66095b681d5d60b39f0b9b507ac447217e2c7e2. 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/HRAA41600029.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc2ee94db8542d86c4ee08c1d6f867498e1d1228c1318ab0a43b66e46d90a4356. Chain 2 (Bitcoin): anchored in block 957020 (2026-07-07T09:18:01Z), 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/HRA042400944.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5ef62ed780a08a7ea6f817d55b760ab8b70155d4a0c945e23d60cf1a18942913. 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/HRA232400044.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x739e8ac8975e9582ef718a6f04fe72b6cf50d78f81efc01143b0c8feee4bb0d8. 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/HRA232400045.