Eva Sylvia Vrethammar (born 22 August 1945) is a Swedish traditional pop and jazz singer. Vrethammar was born in Uddevalla, Sweden. She is the daughter of Harald Vrethammar, an education official, 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 0x56c8893d5cd7d610ab32caa2b3fa20e22d0e4ff03807fa10f7867f10b7c19927. 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/40fccd5a-187d-48d6-a0b1-6162f8336ac8.json and https://artists.proofprofile.net/proofs/artist/40fccd5a-187d-48d6-a0b1-6162f8336ac8.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 0x00922535ee4a9941417a0321999245a885497c5225b907b8a26a87bac612ba98. 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/SEUM70700131.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x91af2af04f23508610d9a969d2cc27e7502a5eccad2d8548b5294b9fc73f3c58. 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/SEUM71201294.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x09cc49207827b6b8e700fa529fa129febbed3450e9ad5b1ffab7864de7f69f69. Chain 2 (Bitcoin): anchored in block 960187 (2026-07-30T01:34:28Z), 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/SEUM71201293.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x17c857f40b866ad74bd50d45fc68c4bee04c280d2dc75d731105889e157548d1. Chain 2 (Bitcoin): anchored in block 960368 (2026-07-31T08:26:41Z), 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/SEUM71201297.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x86f1fbddabb32e397fff60b14950f6d32454c8045b0ddb300634e7b16d921671. Chain 2 (Bitcoin): anchored in block 958822 (2026-07-20T04:30:07Z), 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/SEBFO7207020.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa0d967995ba0ca8862ac59f86b452cbd6210741183f1148cf5138743c0d370d6. Chain 2 (Bitcoin): anchored in block 958834 (2026-07-20T05:55:47Z), 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/SEBFO6908030.
Sylvia Vrethammar / Sommar! Samba! Sylvia!
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb48e66487c83ede121d0d17cb20592b32820711ae1a4edd503644d87e4694bcf. 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/SEUM70600048.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8a8b78ebb2853c5b7a6a7a058e2472d33087c3b0f64a67782e8e83ab26a6346c. 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/SEAMA1300102.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xde1df160bdb0fe0baf2031742d7890220f7b22be977caca78c6581c327b76b5c. Chain 2 (Bitcoin): anchored in block 958517 (2026-07-18T07:54:29Z), 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/DESY11900108.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6c9a3fafed057fcd2b46c065b8400f6b706b584eb1521b76b40c87c598904166. 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/DESY12500031.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1fd67d9c4eb75dbc5e20788733b126e98a1bdd74b5505be362a52d149976e028. Chain 2 (Bitcoin): anchored in block 960218 (2026-07-30T06:57:05Z), 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/SEBFO7105010.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4d9328b28eb69f35b37b8153bb22d3d47b970be8fc94e839f0338b21ee088b18. 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/DEF067909200.
Spanish Eyes (Moon Over Naples) - Original 1979 Live Recording
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7930616189f488a1698fdf7f7dacd5d80a3a95966db7e1aebebacdf011ac9e86. Chain 2 (Bitcoin): anchored in block 960344 (2026-07-31T04:14:58Z), 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/DEF067909210.
Remember When - Original 1979 Live Recording
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xeb0e132d1519e7b2154c51681b6d1fc23524ac15e5d6ddc7b16aa480d8b5b7dd. Chain 2 (Bitcoin): anchored in block 960407 (2026-07-31T13:26:30Z), 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/DEF067909230.