Charles Douglas Musselwhite (born January 31, 1944) is an American blues harmonica player and bandleader who came to prominence, along with Mike Bloomfield, Paul Butterfield, and Elvin Bishop, as a pi
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 0x3adff74f9836b33eedfbb4fa611a9fecd4955db35fdb8904aee2f67cb597517f. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/0acb8532-62f7-49e6-9d9d-5c0648e308c3.json and https://artists.proofprofile.net/proofs/artist/0acb8532-62f7-49e6-9d9d-5c0648e308c3.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 0x1f508d43cb6be8cfd0a8fb64959e6328446f01d4c3767ad5c7fb1e310a60566b. Chain 2 (Bitcoin): anchored in block 958316 (2026-07-16T19:42:29Z), 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/USVG29450539.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfe9e2776d55fe402891f6907c9db677ee8ab9fbabc64138ceb8349e7027a70b6. 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/USARL9078101.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x070cc3a990dd0835eeb56dce80596835e6594670a1d213970e941ac7b0783a1a. Chain 2 (Bitcoin): anchored in block 956728 (2026-07-05T01:43:49Z), 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/USARL9078103.
The Harmonica According To Charlie Musselwhite
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8e8aee2bc6ca314d44e1050860a672609ec9f407e4867d1addb9153f95387467. Chain 2 (Bitcoin): anchored in block 958783 (2026-07-19T23:40:08Z), 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/USBP10301605.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaf5d325f20c16bdc90dae30daba7113db45cc2a6288c091f37386e4fc93d855d. Chain 2 (Bitcoin): anchored in block 956841 (2026-07-05T22:14:35Z), 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/USBP10301607.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9f60d47bd46848d760bc2ca3b424dd88ab61c9e8b9408211d9a540f14e65fd0e. Chain 2 (Bitcoin): anchored in block 956856 (2026-07-06T01:25:57Z), 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/USBP10301609.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x308cbfa236eb904333cee84e04637855784083c294fc00f2564248509f58656b. Chain 2 (Bitcoin): anchored in block 956856 (2026-07-06T01:25:57Z), 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/USVG28950537.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f986d1e18e1743a841a865f749664087fa06ac722849eca12af5e08cddfd881. 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/USVG28950548.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x367b5abc194667bee47697c12c7f6edeb182e194dabeb40dc72ef5232fe2f9be. Chain 2 (Bitcoin): anchored in block 958377 (2026-07-17T06:48:00Z), 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/USVG28950539.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa1a3e631de3de3361f81c7995d488716734c257f855cc358b132c207c0d10aef. Chain 2 (Bitcoin): anchored in block 956639 (2026-07-04T11:19:20Z), 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/USA5X0300001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9a23c24b6e3b6af3439f97ead146c7317881fa101010e706b4e2045190ffa16d. Chain 2 (Bitcoin): anchored in block 958357 (2026-07-17T03:33:42Z), 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/USA5X0600001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe8884b394cbfdb902c170e4ede00a7498c6fc6be77dc941129b72119e06ca963. Chain 2 (Bitcoin): anchored in block 958357 (2026-07-17T03:33:42Z), 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/GBMRY0700013.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3d2eeed309e932b8b9d5fcf274f4d772a0710b1c86bbbc592cb190b2d84560f3. Chain 2 (Bitcoin): anchored in block 956639 (2026-07-04T11:19:20Z), 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/USVG28907664.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x308cbfa236eb904333cee84e04637855784083c294fc00f2564248509f58656b. 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/USVG28950537.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f986d1e18e1743a841a865f749664087fa06ac722849eca12af5e08cddfd881. Chain 2 (Bitcoin): anchored in block 956484 (2026-07-03T10:47:44Z), 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/USVG28950548.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x07f7ca1fa947c30b0f164cee220a148794b8808f544309211ba92854758b8615. Chain 2 (Bitcoin): anchored in block 958817 (2026-07-20T06:31:53Z), 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/USVG28950540.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5b8b585fb16a9c616a3717d3f13906ca47ef3c19a496dc6758e3c14d32aee981. 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/USVG28908997.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x134128a7dfa4466ce0e0724148e340e6d76e30542ef99ba76859ee79c2be9acf. Chain 2 (Bitcoin): anchored in block 958130 (2026-07-15T11:21:24Z), 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/USVG28907554.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x20d168618679cf51c3c9a84306beb395b29ec904f54d8e88450edfc51bfcf15e. Chain 2 (Bitcoin): anchored in block 958728 (2026-07-19T12:24:55Z), 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/USVG28908829.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbface45741813beef20465ea5e2921eda465e7324b8bda85e6c84b15e6878200. Chain 2 (Bitcoin): anchored in block 956711 (2026-07-04T22:48:52Z), 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/USVG29451976.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb0cc30d509b3277f7c45585d1033ee4f55544b8adb41142f3acd7b8544b5312f. 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/USARL1093901.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc5f95a63fa310f51c763a7bbf5b471d4368f673e85cd7541bafc6d052ecd04a9. Chain 2 (Bitcoin): anchored in block 958340 (2026-07-17T02:06:39Z), 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/USARL1093905.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1f17e802018871aa842b2c01c05bc4e93a747c2622bfdcfb12cdb303023b0760. 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/USHM91370458.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5e2c145ced3163da84ee8f84e6a0af74f0aca2897b6b62d39fc117017a06fbaa. Chain 2 (Bitcoin): anchored in block 958319 (2026-07-17T03:01:05Z), 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/USHM91370465.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc9027ac92a1edc1c72108ba37125a21e2cc99ffcaf41229d975eabc91ab21ccc. Chain 2 (Bitcoin): anchored in block 958805 (2026-07-20T02:22:58Z), 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/QMLFE1200022.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc2310e3bfbc63a4b48900321872596f47bbb585f853a2403303fd074658d678d. Chain 2 (Bitcoin): anchored in block 956639 (2026-07-04T11:19:20Z), 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/USARL2200902.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x112508f04eac03ab444615f6025071481f74d6b4f497407ba48364e8f95872d3. Chain 2 (Bitcoin): anchored in block 958601 (2026-07-18T19:27:02Z), 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/USARL2200903.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe82a54da78d638e30b1417b325fdf78bf2b74b0f279096c618bd22dd8fb690a8. Chain 2 (Bitcoin): anchored in block 956656 (2026-07-04T14:03:39Z), 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/USARL2200905.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8ea2910e4bb552eb008e49d5b4e0a68018b93e89da1960d023f19f9a5c37f62f. Chain 2 (Bitcoin): anchored in block 958631 (2026-07-19T00:50:09Z), 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/USARL2200906.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9da923668cb90c2b6cbefcffae036c1de2c8ae038288deed8c83472ce874ea4e. Chain 2 (Bitcoin): anchored in block 956422 (2026-07-03T01:01:38Z), 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/USARL2200910.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x732c903f004e5e3d3de440fc5398b7c683ccda8dd9cbf9772e8a06e88bdf949e. 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/USP5V2500003.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x07b27283a0202319196cd5476ec6c68ba5e65f89207f1e023bc9fbe3beb8f4f3. Chain 2 (Bitcoin): anchored in block 957820 (2026-07-13T07:54:01Z), 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/GB5KW2300362.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x738f619bf67528db90d1d836b6b4c7ef2deb88be7e6add0eddb505a061fa33f4. 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/USEP41731001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0af7c22fcaccf19c7d5b3c3eaf0f6d29b944a41d6b874201fc2a4362bcac1105. 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/USEP41731002.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe3f9529a9b0a76422c494000201417de65fac21a21768cbac2d77196cd83168f. 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/USEP41731003.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc454c7d4e350949624b33597b2f5e217b6948ff8b1170510ddb1d2ebfb3c6ec1. 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/USEP41731004.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd48963d0726231c209af2f78eddd32cb34d2a3996ac740f927d1d38f69052c66. 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/USEP41731005.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x299a96f97428873a1c05ae1f32310ed78259355fe83059e5c16c2b17d983e6ba. 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/USEP41731006.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x67e548180d1c1e908a1974c89191caad8c6a647f984ccb4c6ff1db6615f988fa. 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/USEP41731007.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2ae7ec3ed7923c380b51a08e8b9e45e84ff887c3e4e49381cf257011a2eb7941. 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/USEP41731008.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd2354ec9cbe630109f9c243a71de870e10ed42c7ba808fc9d35f4405be85f80c. 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/USEP41731009.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4eb3b93dcdb7915f11a18e2ce7ec69850154b08da4d1f382fd4a1abc9bebe336. Chain 2 (Bitcoin): anchored in block 960404 (2026-07-31T13:06:57Z), 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/FR6V81067850.
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