Petr Kolář (born 27 September 1962) is a Czech politician and diplomat, who has served as the Czech ambassador to several countries, including Russia (2010–2012) and the United States (2005–2010). Di
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 0xd78b90a644ccf3530ed1f3ef5cc35e1ae62da13de1a0496809abc945dfe599f1. 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/22a78212-3f76-4bd3-975f-f2b827521497.json and https://artists.proofprofile.net/proofs/artist/22a78212-3f76-4bd3-975f-f2b827521497.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 0x248b542dcc98d9f4c12d5822136fc890af6eadbd7197526d4c0ebbb3ef8c1624. Chain 2 (Bitcoin): anchored in block 958410 (2026-07-17T12:18:07Z), 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/CZA540252601.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3edd3be702abe6345ab3e7dd0b3558c6d20173942d2f8d56b5fda2253b6b02e7. Chain 2 (Bitcoin): anchored in block 956776 (2026-07-05T10:59:37Z), 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/CZUM70500044.
V Lucerně (Live At Velký sál Lucerna / 2006)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x40b9ee0c2f27126bf392918ca874300ca5d70706515b27c30c0b5c520c4e870f. 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/CZUM70700396.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8a6c77738f100e58d51fed98c3c767d2065fd2a2bb2a54dd95e698b64c6d6cd3. Chain 2 (Bitcoin): anchored in block 956826 (2026-07-05T19:27:56Z), 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/CZA230600596.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc5aeee108498a0b36c26a62893249ed1231f703e50e77cd7a67a45ff22d0450c. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/CZI362000037.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x347983271c202711f13665b9da159c6ef66eeb0f718f9ae34ee738597a2f0ed5. Chain 2 (Bitcoin): anchored in block 958420 (2026-07-17T13:33:01Z), 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/CZA232401029.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa76cf058e92355fc616e2ff450d040a684a51c6e1b6d249f8eac1ad4f8de0aaa. 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/CZA250900049.
Muz se zeleznou maskou (Original Prague Cast Recording)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xed4a29124e2f491a2b1171a54b02dd4e4f2c522aa31bffe6f1dea0ba95f76263. 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/CZA231700397.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x02682ffadf7d688585ed7b6e83580e2ea42570ad7bc4675e2cb4348947cf1bff. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/CZA231700396.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xead6f1bc5731eec1b1aec7b461ef4f08a32f715143ec411795f6ea7e56814285. 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/CZA230200044.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8e7696905f9aaadd9a8204caa39a5bb6e5c42e2046db6c9da5ff3a2e0e944158. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/CZA230200048.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x59710cac5527d975adc698756acc7cbed20f45e9102dd0222d30e06ebdd09c01. Chain 2 (Bitcoin): anchored in block 956351 (2026-07-02T11:38:34Z), 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/CZA541113610.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf3d5829c0a3cafabb8740a5bb11c6d2b37b6fc7381640000985dd54fdca02ce8. Chain 2 (Bitcoin): anchored in block 956349 (2026-07-02T11:34:59Z), 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/CZA541113614.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa243d2c9bdfaf967e0508ec564d860037225afcf25f0dbda5735acf52c2c65bc. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/CZH681400045.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9dc288acef1980a5dfd646595e13d383700c5a42e7a3e43eb3e3e714e7e2ba7b. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/CZA231700400.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa9617bbea1907ee543d0e8f2e8ed75357e56aa7a1f3951914a48b2d8e50e4608. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/CZA231700412.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x352b848b2830e0d6757bf13e18b97f1145266e41960a7d040e1eeb9c645c0151. 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/CZA231700414.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2671151a20620f85a93b69ed6f93c33c43492b430b4258591184047932ce43ae. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/CZA541010303.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf93e4f1958410f957ea216839469d2e7aa00c7b9669c72ea83b96ef735668152. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/CZA161441399.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x59710cac5527d975adc698756acc7cbed20f45e9102dd0222d30e06ebdd09c01. 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/CZA541113610.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1be07d67df8c8fc316c1c361cc80876917c608d8b27dc5b2da87da41f0b54af4. 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/CZA540255421.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xead6f1bc5731eec1b1aec7b461ef4f08a32f715143ec411795f6ea7e56814285. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/CZA230200044.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x31a8de69351ec28fd4683b080c4557ad1fd9b30b6f0a57f4cda032bce7b30bcf. Chain 2 (Bitcoin): anchored in block 960199 (2026-07-30T02:30:29Z), 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/CZA541113612.
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 0x14566a7afbeddffe2a58b27d2c21355034ac5d24fed9e18810d5ad8f72893dbf. Chain 2 (Bitcoin): anchored in block 960468 (2026-07-31T21:25:57Z), 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/CZH681400050.