Oceán is a Czech musical group first active between the years 1985–1993, and again since reforming in 2011. The band's best-known incarnation consisted of Petr Muk on vocals, Petr Kučera on keyboards,
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 0x553bd42266b3cc615362998d28fb59fe55902b5b94b40c5a02ef6ed0eeac44d1. 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/e0681be1-2d2e-4a60-818f-80478be99f61.json and https://artists.proofprofile.net/proofs/artist/e0681be1-2d2e-4a60-818f-80478be99f61.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 0x09411fdfa5c3cf3f05648ffc757aa6d1aefb52158b193f0b359c008f52caef52. 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/CZA239900262.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7d74e0a263a53ccd1079b704ae0854eb5e3a829269190747eb30f94b9e4e84ec. 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/CZA239200101.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0658bb51509c034c9d173f39106e9d593a8e93c24ad23fc518b56e1bd44f25ca. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/CZA239200102.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8c9546aee6f3f16101cfd1cba07cdc52207bf7ab58126e5266397de71a0bf44b. 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/CZA239200103.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4824ea934ce69d0ce8d540c1e55d08be83b5b28997df9ccc0e38a4d0357f4746. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/CZA239200106.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf57224b7621e532f961dcfd91c8b249d25136675b1a986b7bcbc4286cae9523d. 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/CZA239200107.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbff73a3afb656bbb59f7e7e68ef9a067574e32f779c1b5dcc8b48738df7c754e. 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/CZA239200108.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4fee5bc2f1a1d83c42bed9c33eb87547a34a9dc44a07b95b0f6ffc555b7e9bc1. 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/CZA231100626.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9b0279ff237f79d1af638f9ba8e84b400eb31767ff7c9158c19c4aa4e79b5c7e. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/CZA231100625.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x89041595dac2f0b9303ca03c724c2cd09cf832de161c203cfad04bb94daddced. Chain 2 (Bitcoin): anchored in block 960207 (2026-07-30T04:47:22Z), 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/CZA239200100.
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 0x230de2bed374fbfdd1e262fa1831686d96f5857894258625b0ca2487a2133ecf. Chain 2 (Bitcoin): anchored in block 960144 (2026-07-29T21:09:47Z), 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/CZA239200104.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf3c9edc9f5f6b8be0ac1d8ec6ffe63d393824f3c9ae7ad44b49575f9776b207d. Chain 2 (Bitcoin): anchored in block 960121 (2026-07-29T15:22:21Z), 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/CZA239200105.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d18c27ce849023b5a717ea81c3616c0cf66519e8812874d5df0af34ed8150ea. Chain 2 (Bitcoin): anchored in block 960500 (2026-08-01T03:13:03Z), 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/CZA231100627.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdc76c9f2fa34de5bdc95747b8b8f66e2b0f9159ae2a834b88281f7c19cf2838d. 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/SKA129026601.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x41480d27d3e461750f6b5397a40eb3c3b4b2c412799386d62e3fbe348b9ba4d2. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/SKA129133804.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9734033d51280fd7053daef0d6121cc698c1e2280d6395126b9c2083a9de8853. 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/SKA129133807.