Sigvard may refer to: Sigvard Bernadotte (1907–2002), Swedish industrial designer Sigvard Eklund (1911–2000), director of the International Atomic Energy Agency security council Sigvard Ericsson (193
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 0x383094b8bb16c2ada633b71bb9a7269a84bf6e95f7b6fb46867992d57bb03ba9. 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/722cce41-a861-4dcb-9540-ea9f136244b9.json and https://artists.proofprofile.net/proofs/artist/722cce41-a861-4dcb-9540-ea9f136244b9.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 0x043b5b2c9bfd68c52982f4ee15e2d4984bc6f4d79021598542004e36066a76f1. Chain 2 (Bitcoin): anchored in block 957638 (2026-07-12T01:56:41Z), 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/QZK6L2078455.
Bereden väg för Herran (Prepare The Royal Highway)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0719d9160b7b794a4347d8caab081fda669c9009129f7b5fd299ae7b98b724d3. Chain 2 (Bitcoin): anchored in block 957741 (2026-07-12T18:30:59Z), 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/QZPLR2081640.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d9f34c9841090d51a910059b10a9ae56246be9ab22cb54cffdeb217f4287513. Chain 2 (Bitcoin): anchored in block 958942 (2026-07-21T00:24:07Z), 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/QZFYZ2176644.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc123d68cba11715aef54a7c61b8d25cdb1686457b38508ac54deaadae7897780. Chain 2 (Bitcoin): anchored in block 959024 (2026-07-21T15:31:18Z), 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/QZFYZ2176646.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa4913550eb2f743d4669c5cc4ccf8959f68a343dd2269e02f75540b60dd6b565. 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/QZFZ42127675.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0faa9083e36ea34efe8fd5fda1c33bbbd9f37e7748a61c281fd99cda173509ec. 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/QZDA42188635.
Rest In My Presence - Solo Piano Version
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf7327a5b02440b2a35dbe51dc6a25d9eefe1ed49f29e916b72a3eb00d505a497. 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/QZDA42188637.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe127ff7ec93c92ed8c9a560d0c49c112ad80be1652ec31661743c1fb6183014c. Chain 2 (Bitcoin): anchored in block 957650 (2026-07-12T04:18:57Z), 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/QZES52134570.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf8ae64ec664925994f4145668d2570ad0e6d1b1a518fe94a2a3a81433fc1946b. Chain 2 (Bitcoin): anchored in block 957642 (2026-07-12T02:46:48Z), 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/QZHN52120101.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4887be549fad567ccf73ee7f4fa06440c9b7bcfebf1a1a538d3a32c7eb25bfce. Chain 2 (Bitcoin): anchored in block 958689 (2026-07-19T07:11:11Z), 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/UKR6V2113089.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe56888a2285fb5b734910546f97cdf6f729a8e9ff21fdb17a0e971cfd38faa47. 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/UKR6V2113997.
Jag lyfter ögat mot himmelen - Felt Piano
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1291179b1ceb3cf3fd0612bb24c0d76359e25fd25714da179644e87bd97c71be. Chain 2 (Bitcoin): anchored in block 957647 (2026-07-12T03:57:41Z), 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/QZFZ62251915.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1b3941ce5753b066a980732f09c27d517f7fcde430eab6fe6404e11c6ba44379. Chain 2 (Bitcoin): anchored in block 958395 (2026-07-17T10:10:33Z), 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/UKR6V2210596.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa71dd57230c97f1969ce4ec2a15904edc6a8bccdf35e848f4c0c0fca900d8a44. Chain 2 (Bitcoin): anchored in block 958690 (2026-07-19T07:14:39Z), 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/UKR6V2213124.
Jul, Jul strålande jul (Wonderful Peace)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5453f29f629cd777c445b7ef06e3d0b3aa0e7be5b9fd5a757617a5ffff6bb7ff. Chain 2 (Bitcoin): anchored in block 958058 (2026-07-14T20:20:34Z), 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/AUMEV2306600.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc05a825f5054b4ce6fad4f44580a4c7976936120b25640ec05ac8b54937f2012. 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/NL4WT2300111.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa07bacf7b9d573d1f7e3f8268e0c360c9453da28036590cbdf483bc872c958fa. Chain 2 (Bitcoin): anchored in block 957644 (2026-07-12T03:18:52Z), 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/AUQ9D2404753.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x17a58321740aa3f12bca0b30702ad600a9f6f134cbbabfac342487d2aabbc9e9. Chain 2 (Bitcoin): anchored in block 958060 (2026-07-14T20:39:42Z), 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/SE5BU2511492.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1f67249ac8c520cfedf265a23a89d9af712f2e71b41ab4c53143084244b97182. Chain 2 (Bitcoin): anchored in block 958058 (2026-07-14T20:20:34Z), 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/SE5BU2511486.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x05898fb3732961bc1ba9d5f9e3a68e2825321334959cd59468eddf4125c34b80. Chain 2 (Bitcoin): anchored in block 957851 (2026-07-13T11:26:33Z), 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/SE5BU2524436.