Darya Yevgenyevna Yeropkina (, née Zoteyeva (Зотеева); born 11 May 2000), known professionally as Instasamka (Инстасамка; Instagram + 'female'), is a Russian singer and rapper, TikToker; formerly an I
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 0xbe8526066539cd00a0232e3820b5d804b2d505d91a88670c712cdb9cb612463a. 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/9fc203d2-dea0-430e-92cb-95e7240f1350.json and https://artists.proofprofile.net/proofs/artist/9fc203d2-dea0-430e-92cb-95e7240f1350.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 0xad5b6a209a3243b74d535fc5d13d3e571830ede7d628a187e3652a0ca586230a. Chain 2 (Bitcoin): anchored in block 958362 (2026-07-17T04:32:48Z), 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/FR96X1937058.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x54b70d46aec2a685790dbae06e275c1f430abbc0ba8ae3de034b1fb092d4ec8e. 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/FR96X1967044.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf23727f54c3305d09023850a050eb4a879d690f4eb8dbd708fe6abad19843a5c. 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/FR96X1974705.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd70f3ffcbdc3207cd8dc9525ad4b7c675f43e159eb2f7489a208e16fc43be3e9. 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/FRX452042343.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc783ad351bd2ad2601d654505e4e92f1bf1df3c16115bb3817b4b60bcfdf6b57. Chain 2 (Bitcoin): anchored in block 958771 (2026-07-19T22:11:51Z), 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/FRX452042344.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9b3561fdc6a8591ed5278c96c245ecfdd29cbd94b298c5795672e0e012016298. Chain 2 (Bitcoin): anchored in block 958907 (2026-07-20T18:34:10Z), 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/FRX452042345.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x592ae5f842a01585859764417acbb6aa82e863be3f523657b18288e7bdc4f93e. Chain 2 (Bitcoin): anchored in block 958720 (2026-07-19T10:53:46Z), 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/FRX452042346.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x155b4a0f35fbfddc0f94017671a0614e53449d505044ae316ca2d7d2a3ff1926. Chain 2 (Bitcoin): anchored in block 958975 (2026-07-21T06:12:52Z), 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/FRX452042347.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf1fad1f74ad8f3b749149a78a2149606c7892ffe3d5499a244c9d5d5daf772f4. Chain 2 (Bitcoin): anchored in block 958996 (2026-07-21T13:39:28Z), 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/FRX452042349.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x01a6e4df90bdfba271bf0160c3879dfb8a27d289ce5522f857692b13ca90abd1. Chain 2 (Bitcoin): anchored in block 959024 (2026-07-21T17:08:14Z), 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/FRX452042354.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc64b5c1ab958e9294936e96eb4327b9e1116cf207fde8dd311c0d363a6636519. 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/FR59R2032949.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe93270b6e4fb19ee35550dba91240e9b9c9baf568316239944401b354f9efe06. Chain 2 (Bitcoin): anchored in block 958137 (2026-07-15T11:47:24Z), 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/FRX202246907.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x08ba90c4f5bbee30d4b2c429d6e0638f0a6d1fdc4841e48a170d834b6d877677. 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/FRX202246908.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xea995ab63e5f1c62c345f02f426f67b87f03e6eb7995b92fc05a1937fe9db99f. Chain 2 (Bitcoin): anchored in block 958176 (2026-07-15T19:46:23Z), 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/FRX202246910.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa10377fa31148e10db677351f1b4c5db3e3d369cea9f7f15542ce2b4de8f91e9. 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/FRX202246913.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe218d1dfaed0c000f0de8b61bbc815a6dad289dab55454ec899091a919fee461. 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/FRX202246916.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xed6e067ffe1f4d0c5ce8da18d902314bceaaca2cb73f6a9f92062ed461e22e27. Chain 2 (Bitcoin): anchored in block 956790 (2026-07-05T12:31:54Z), 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/FRW242303060.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb5abd5f0186cca90557b58bee59d0a8da67f9c066efe6dfbff22cc648f909880. 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/FRW772315954.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5a4c5906e8ab129f18d3774027851b3060f5368aea15a6582cd90c1792c77098. 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/FRX452308829.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3c5b45ef9a786892f8148c13e00ef874481a5f01a6c572f5e458d8d9747bf822. Chain 2 (Bitcoin): anchored in block 958137 (2026-07-15T12:08:12Z), 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/FRX452308832.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd19ce3f0db2873e7794fa65b106dc5ed439034b21eefff40a5c2362a659afff4. 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/FRX452308833.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x57eb6cdf10c9daaadcbe359abda2a3cb08e39b1660d0470429b1c0ca635942ea. Chain 2 (Bitcoin): anchored in block 957888 (2026-07-13T17:43:59Z), 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/FRX452308834.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9afe48fac2afbe884583c62463121bbdb8d5b23fe8d6479d6af44c557a3c1dc9. Chain 2 (Bitcoin): anchored in block 956476 (2026-07-03T09:04:44Z), 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/FRX452308835.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x82397a060fb20298dbaa0b061a51073c983168087cc0d1b6f71b16fb1847adff. 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/FRX452308837.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe0cf5235cd78b8a6eae7ebe99f55054eb9eede656326aae2c2e2c909f6c42f0f. Chain 2 (Bitcoin): anchored in block 958362 (2026-07-17T04:32:48Z), 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/FRX452308838.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb2ba66afa60ac90fecccc7d302ceec6b4bc6b3af8bfc71421feb727132e1a4c5. 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/FRX452308839.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7a0dff001ebffb27c5c7175abbd13276ce9b094cf72b63812d088f99ab257fbb. 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/FRX452308841.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7508ce4c9cc6688e9ddf294d048a49c60c5447aeb04149b9e6dee7fbad69581a. Chain 2 (Bitcoin): anchored in block 956576 (2026-07-04T02:06:47Z), 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/FRX452308842.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0a87a948c410a6416ab75990eee29d453df98283e4fa566d724d48cfdfea57bb. 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/FRX452308843.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbdf40f2eaafc119d523f1adfea93294ecf53cb1f5d280f05eba57a52baf060e8. Chain 2 (Bitcoin): anchored in block 958319 (2026-07-16T21:49:59Z), 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/FRX452308845.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe002b7ce24f870acc39f831de2e258cdf0f981bd03da573ce8a818adee90f331. Chain 2 (Bitcoin): anchored in block 957805 (2026-07-13T04:34:37Z), 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/FRX452308846.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x843f38c4d3ccba6fc5f8e5dac983b50ba0173b509a05162e24b0d45b8971ccdd. 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/FRX452308847.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe457407c566f3636e4d2c9595910fd186eee934b0e673484368d7260788e2c29. Chain 2 (Bitcoin): anchored in block 958489 (2026-07-18T04:13:26Z), 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/FRX452308848.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8b9f49707747395df71e532daac0a2891fda023a5d176b059f6b432221494b24. Chain 2 (Bitcoin): anchored in block 956790 (2026-07-05T12:31:54Z), 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/FRX452308849.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8c78ea050f50d8e46d48b3b8baed3f63947a84d04d4b36e5f7448718ad6984d7. 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/DGA0L2398889.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x63d5a6d71cd77002c1f08952781208230f0601a66b5542d8cf6982e661e1e3fe. Chain 2 (Bitcoin): anchored in block 957805 (2026-07-13T04:34:37Z), 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/RUAGT2477620.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xef43e54440ef7f31549bf0dd831b01c04a543c6c8c85d6fb9fa26919dbcd07f3. 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/CA5KR2131960.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc7110ab15ff2f447010e5c0bede5ba389cf99ec947076f044caed7dcaadaca7c. 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/CA5KR2131909.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6c3534083eda620bda9a42d977fee2e107cecc413b383c62f7f979ec60524375. 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/CA5KR2131905.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc7110ab15ff2f447010e5c0bede5ba389cf99ec947076f044caed7dcaadaca7c. Chain 2 (Bitcoin): anchored in block 953536 (2026-06-13T17:25:41Z), 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/CA5KR2131909.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5cf8dbeb799454c36911130b250f3f66e284fd492b104961a071f2d1508ca2da. Chain 2 (Bitcoin): anchored in block 953536 (2026-06-13T17:25:41Z), 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/CA5KR1981274.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x063dbdb3576ebc5532f39cd5f8bbb2a5c356bdb5a36d9f0e6304a2ec1db1286d. Chain 2 (Bitcoin): anchored in block 959123 (2026-07-22T11:35:32Z), 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/CA5KR2131914.
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