Etkin (; Slavic feminine: Etkina) is a matronymic surname of Ashkenazi Jewish origin. It derives from Etke, a Yiddish pet form of Esther. Notable people with the surname include: Bernard Etkin (1918
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 0xec88f65b547bd8d51e2e86420909a1368177d34bfc9f71cf0f2ecf0d1cd134c6. 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/4a8da014-4ca4-46f7-acd2-39b7a2e8f9df.json and https://artists.proofprofile.net/proofs/artist/4a8da014-4ca4-46f7-acd2-39b7a2e8f9df.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 0xe0697dcf9358f6a911abffff0325a4d2b47b768e43a49236bee32c8f679cbb80. 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/TR4850700150.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4df3d41e938e33c7b6ddb26b256907c6b98256f8f6dc841962aa5fb82e013c71. 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/TR4850700151.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x334f77e7281e1c54ab78da4659c6fb15e231ea1c2502766bc3af9e02d1c5d62d. 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/TR4850700152.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xad97bd00c2c1eada8cc39c4ada06b90ea8daf09beeba1e9d6e79155b68917013. 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/TR4850700216.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3d9e61d5b531a1566b687bc4dc594ef8f4b448ffea97f9b482aa13527435b213. Chain 2 (Bitcoin): anchored in block 958897 (2026-07-20T17:30:52Z), 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/TR4850900124.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x56affefe5d8b766a4265c6dd467ebc4eaba85cc38c28956aad5c918fd482d98c. Chain 2 (Bitcoin): anchored in block 958771 (2026-07-19T21:04:43Z), 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/TR4850900126.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0292525c50eba6eafa30ec7de5b69569f3343a5b1f6cfa560d5a8d8fd65568dc. 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/TR4850900135.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe565c332fb1945c432b246deed4c96e26bca44849c11bc6f36606044700640c1. Chain 2 (Bitcoin): anchored in block 958212 (2026-07-16T01:54:03Z), 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/TR4851400692.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x54d9eeb4dc978395115c68da1ab3230adcc26c6e9eb15594c8000adfb3c6d81d. 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/TR4851400693.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1f9a629293b2d75d883cd028d054a83067eafffd3f4ee19eb1dea619f146885c. 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/TR4851400695.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3f94d1fc852617e91faff6bdd3e76bab650cdd56f1167a2f724219c0abdb7c2e. Chain 2 (Bitcoin): anchored in block 958696 (2026-07-19T07:45:31Z), 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/TR4851400701.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc2f375d9839af7c74156a93d2489708d13dd132599c886900fe1ef164c61b1a0. 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/TR4851800029.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6e990484017b426bf6c2d851352e10b8832887f879d37f610784eba5647fcd87. Chain 2 (Bitcoin): anchored in block 958691 (2026-07-19T07:19:31Z), 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/TR4851800026.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xef655036c1ab17995658fe878ccb896a0d195bd76070b6e44da5ed89aa244902. Chain 2 (Bitcoin): anchored in block 958444 (2026-07-17T19:12:23Z), 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/TR4852000004.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb8b6106e97eb34d4138077ea0b4bf3cb1bdea4ed12ca091408b4431f07bd884b. 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/TR9242200023.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x01b602edc90fe3677c31e2163dfd9ffb96ce39651da6193675d749912fefd362. 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/DGA0M2383835.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x33805b9b2b6a84fe0bf04312b54220bc5ba964c49d6c63039d2a57c0a1841089. Chain 2 (Bitcoin): anchored in block 958256 (2026-07-16T07:22:18Z), 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/TR4852500027.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc0042e48972331c65dde0a61d2fdcb2940717e2147e6df40245e4179aad8c474. Chain 2 (Bitcoin): anchored in block 956551 (2026-07-03T21:18:05Z), 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/FRX762588570.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2912cb5c3c7b23d63fa27ed5a7abfe5cf4112109f098336ace874cd4b564bdf8. 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/TR4852500048.