Mārkas Markūlis (; born 31 March 1993), better known by his stage name Markul (), is a Russian hip-hop artist who creates deep, atmospheric music with melancholic lyrics that combine elements of hip-h
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 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 0xe886d6d75658df713499039d1f421e1c021caefab4ad68df5a3162daddb43bd1. 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/f211bcca-7591-4c9d-b3ac-81b814653497.json and https://artists.proofprofile.net/proofs/artist/f211bcca-7591-4c9d-b3ac-81b814653497.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 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 0x0e0a25fac36239f5fce4b4d23d8f482ae400ac90380b2bbe34abf1dd7bcc0570. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/TCADJ1721515.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x95be888ea5297dd1bdd2687392ccd41671a3363d41602c2aeb968925f5aaed0a. 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/TCADJ1721386.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xeb759f99a878c7a649f088a1207bbef69545b4aa3163a051cfffcfc139395bbd. 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/TCADJ1721391.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x625891279b411b26cffd12f2d85b656e64459f8cfe198bc5cfd643e71a5a0bdd. Chain 2 (Bitcoin): anchored in block 958850 (2026-07-20T08:32:30Z), 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/TCADJ1721416.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xeb569e17abd9fea61f43c02a165b96a62b4909695ec9b095e23a84bb40b1aacf. Chain 2 (Bitcoin): anchored in block 958796 (2026-07-20T00:01:46Z), 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/TCADJ1721514.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x67eb4f1bbd5b3b9291a7bc2a99d52751f2cd7103d6b380ba15928e013bd440f5. 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/AEA0Q1854818.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x91b2561f544880d0334fa41f91e6c0d0b3c91de309e914180612d730e5761025. 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/QMDA62127012.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb87b6d5e0598c8c43471944bd9f7ea4b249e08611e13f00d683ab24c7b6771b0. 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/QMDA62127036.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x290daf798c249407cd697809f7d53260f74722fd64e66bcf44173cee25029f08. Chain 2 (Bitcoin): anchored in block 957801 (2026-07-13T04:17:08Z), 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/QMDA62127293.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0d1f9c780e33c72b0e67737e3a8455fb4b89ee609e92eaeff16c3977c713e7a6. Chain 2 (Bitcoin): anchored in block 957867 (2026-07-13T14:55:20Z), 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/QMDA62127304.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5537d1235a09c8a3233a650b7a24326920cde4a004903b0066a1e3ece72f2d39. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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/RUB422201876.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6e3e93665d82bb9fdb6f17d77fea79cc6eddadffb0f5fd414ae556176ac74564. Chain 2 (Bitcoin): anchored in block 953513 (2026-06-13T12:47:07Z), 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/RUB422201949.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa6748381026cabd5382e48f8af690dc5130fe9e17614f1f3fca881e96745c9b7. Chain 2 (Bitcoin): anchored in block 960334 (2026-07-31T02:19:15Z), 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/TCAEB1920923.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc1b0f5ed673689dcce698eacd9c1b62e4c6b62a93f429b69967d213e9a5acb8b. Chain 2 (Bitcoin): anchored in block 953513 (2026-06-13T12:47:07Z), 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/RUB422402445.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x63cfbce67d850a34889e521f61946d30a72db8f84f271b13285129e42a0afb64. Chain 2 (Bitcoin): anchored in block 953513 (2026-06-13T12:47:07Z), 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/QM6MZ2368360.