Kristofer Niklas Greczula ([ˈɡreːsəla]; born 27 February 1992), known mononymously as Greczula, is a Swedish singer. Biography Greczula was born in the Karlskrona Municipality, where his father was a
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 0x5ae6a3281a26f8478590689dd3f660c8b8075c365811fc9882d938ed700c3ea5. 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/52fa2141-7a7c-453f-90a9-c2069b955512.json and https://artists.proofprofile.net/proofs/artist/52fa2141-7a7c-453f-90a9-c2069b955512.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 0x6dbe282085353f042ae915c5f66fb1c1e6811dbce98fad6c5823c49324334146. 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/SEVJH2102501.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd146fd649cffb4248063c24c90438eb4fe586c19837d0496b0c288921034d655. Chain 2 (Bitcoin): anchored in block 959105 (2026-07-22T06:33:30Z), 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/SEZ862100140.
Something Outta Nothing (Blah Blah Blah)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9e3dd4c134106eb2a8fd33787da1547b090928ed5599b4067a690eebf18d2b58. 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/SEVJH2200301.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdd344cf42167737cc445184a64bf815eb02d523b2ebd4d3d6d5290a4834daf5d. Chain 2 (Bitcoin): anchored in block 957751 (2026-07-12T20:41:42Z), 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/SEVJH2200403.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7ed0f473dff487ac74727c01a7521045776f3bdf6df68943cb82258a6e8b05c7. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/SEPQA2400214.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7ed0f473dff487ac74727c01a7521045776f3bdf6df68943cb82258a6e8b05c7. Chain 2 (Bitcoin): anchored in block 957043 (2026-07-07T13:52:39Z), 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/SEPQA2400214.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7ed0f473dff487ac74727c01a7521045776f3bdf6df68943cb82258a6e8b05c7. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/SEPQA2400214.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7ed0f473dff487ac74727c01a7521045776f3bdf6df68943cb82258a6e8b05c7. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), 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/SEPQA2400214.