Zenaida Gourievna Booyakovitch (1924 – 18 December 2016), known as Zuka, was an American artist of Russian descent who lived and worked in Paris. She was awarded Chevalier of L'ordre des Arts et des L
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 0x967feaeabb7c6a58e08d9120bf68fdcc5dc6b0acf9d950d95ff9e8b5ed05c2e7. 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/70cd183a-71c8-4c02-a690-610879d8bfad.json and https://artists.proofprofile.net/proofs/artist/70cd183a-71c8-4c02-a690-610879d8bfad.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 0xd48b10b55cb48ebeacdc1f33d0f89e375293a554a418bd1adf01c0b18ac5d985. 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/QZWFL2492828.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x504c12cd14a6bef6b505654a5498243be94cfff601304d132aeb5f7ef20bbbae. 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/QZWFL2492829.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5435d6038aef44f4ab278e44ecff843fd7a3712897c45760da61d7662e20d74e. Chain 2 (Bitcoin): anchored in block 958300 (2026-07-16T16:14:30Z), 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/QZNWW2461214.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd991163bda98ed73f9a384a28798743060e2aa417109317ead1b0c32b42eb12b. 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/QZWFL2492831.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x33f83cf2229b6c463e8b254e7ededb9f0c274b56131cb9aa69a10a736a684856. Chain 2 (Bitcoin): anchored in block 958654 (2026-07-19T03:55:30Z), 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/QZWFL2492834.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x29986a7841a8b4c4f8d9696bbfbcaf1b6f31b2a9ec94c010ca9cb21d19b63e0b. Chain 2 (Bitcoin): anchored in block 958324 (2026-07-16T23:19:27Z), 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/QZTAW2537167.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd46553956d6a5c1efb13e4bfbcd7ea10f27e5d01443cf93af5b1d51dbc50cbee. 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/QZTAW2537168.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xde9045b0afd0af102ef569a9092294b89c003cc354fa4efb7d584d9511a94229. Chain 2 (Bitcoin): anchored in block 958245 (2026-07-16T08:00:06Z), 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/QZTAW2537169.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x68267a699a266807b9e87cb7afea19a8ee1481b1ce3101ca61e32650271ef662. Chain 2 (Bitcoin): anchored in block 958473 (2026-07-18T00:52:36Z), 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/QZTAW2537170.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdca469ebdc654f3a7f6f2398a1bf012c61649e73860fc5133b4f85a41e2af1e3. Chain 2 (Bitcoin): anchored in block 958349 (2026-07-17T04:47:03Z), 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/QZTAW2537172.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x10abe45af0568637651324dd1b11c72b41604c3542dec0345662b86c5ad542fa. 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/QZTAW2537173.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x95fe43dc0b2c2d78bffa570d7411fec2502e6b739629f5a97dcbd6127e758a49. Chain 2 (Bitcoin): anchored in block 956420 (2026-07-03T00:42:11Z), 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/QZTAW2537174.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x99dbc4f80c871af50fd9080ce25091b2ee8c08a87c6324a5931083566da6fabb. Chain 2 (Bitcoin): anchored in block 958802 (2026-07-20T01:04:02Z), 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/QZTAW2537175.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xffe753598fe88b022275a97cc01eaee43f64a463e91b76b054b0f2bbabca408e. 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/QZTAW2537176.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcd35f68c83c997aa90a7e5472ac0a00e4ef706a48d486e18ddd2f7296183307e. 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/QZTAW2537177.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4e4cd3f3a45a355f5c005ef15cad50063609264c567eb1e9ce00bd26609e1dc4. Chain 2 (Bitcoin): anchored in block 956738 (2026-07-05T04:47:21Z), 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/QZTAW2537178.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x34e77631cd7cc9eda829339e36f1b2d700bea2fd0182e35d5649afa45eab156c. Chain 2 (Bitcoin): anchored in block 958765 (2026-07-19T18:01:47Z), 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/QZTAW2537179.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdde068c2c7cd9661b2a6a29c72135d10073ff48eec3f4bc340a5fe7aa1f01f89. Chain 2 (Bitcoin): anchored in block 958166 (2026-07-15T16:44:01Z), 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/QZTAW2537180.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc2c77e0f5909ca35ba0362f113be788399f160e552fb5033f824c79d2978d986. 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/QZTAW2537181.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3ba0db74d6672e2b17e54f9c1c466226b91dc1ec039577653fd98d747a387bab. Chain 2 (Bitcoin): anchored in block 958951 (2026-07-21T04:29:39Z), 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/QZTAW2537184.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2a6ec8ed6732fd491c22fda5cc8f543997329dd6904e642f73883701e63fb6a0. Chain 2 (Bitcoin): anchored in block 958300 (2026-07-16T16:14:30Z), 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/QZTAW2537186.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbef868488718a8abd4e008e6ee5689529a152f12e7f58cfd37b839e2eca6fdff. Chain 2 (Bitcoin): anchored in block 958544 (2026-07-18T12:14:37Z), 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/QZWFM2548797.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2ca11cdaf9fa631a2fa7cb77b13d43a8ce52622c338ea93e8a74229ad43ab024. 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/QZZ7K2592681.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3977d55f3676f6574affcaff4f183c7da70aa0230cf7a2e18c9f4a8ec72309ea. Chain 2 (Bitcoin): anchored in block 958650 (2026-07-19T03:36:41Z), 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/QZZ7K2592682.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9f12754be7c67802891a6cc07bebb5683b32ab68e2afd39db6a02c628d282dd2. Chain 2 (Bitcoin): anchored in block 958802 (2026-07-20T01:04:02Z), 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/QZZ7K2592683.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xab9e7573e3aadae7577e2f2d8e7b8ba59fa5f915b4ea541bdaf97c339e3b2c29. Chain 2 (Bitcoin): anchored in block 958796 (2026-07-20T02:36:59Z), 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/QZZ7K2592684.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x702a4bfe96cef08d2c2e5ac251d058997a503b5ed2757f6428b80a79cb3400d0. Chain 2 (Bitcoin): anchored in block 958853 (2026-07-20T11:37:34Z), 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/QZZ7K2592685.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x439eb01ae6203d01a0955401baf95bcef1623bd812d957b3eee385deb7af1f2d. 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/QZZ7K2592686.