Family Four were a Swedish pop group who recorded during the 1960s and 1970s. They were made up of Berndt Öst, Marie Bergman, Agnetha Munther and Pierre Isacsson. They won Melodifestivalen twice, in 1
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 0xe80649bff4d534d36b90b57cf21854814e77eb2a5a8c745c48337d94d34eb928. Chain 2 (Bitcoin): anchored in block 954342 (2026-06-19T03:22:39Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/892b3d04-e0a9-4e5d-b541-80991d77d897.json and https://artists.proofprofile.net/proofs/artist/892b3d04-e0a9-4e5d-b541-80991d77d897.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 0x8f909d0f9a92fde08c32f0782edb8408e5465aef594f9591868674bf9af683d8. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/QMEU32022969.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x505de728d72b42a39572b4b2f9457219abe88fa51212c5a53ec36845fbccb881. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/QMEU32022970.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6032cf68dc7bef2cdb6d18d82443cd6b3a0fcfc2a8382a0de1bdb81c1b1902e4. 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/QMEU32022972.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6694045036b1de7903235c8d13bc828fe7dd51dfe3f9eb9eff9dc38f924aa902. 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/QMEU32022965.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbc96c547046e7ae891fd6695e29b884c8694b00d4e0bc8e8f8056db12851b056. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/QMEU32022967.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x566223412a7644216115be5413d0b4f9088cb877608dfaaa9fea949d73547567. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/QMEU32022968.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa5bf2d2b416f19e1cd2c872a4354f82559393f5787e9963aece511f0a0b1b669. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/TCAEH1985463.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1d7b01bbe69d841adb0207ca6b14a85a7d73dee6ac0e760637395735e500caf9. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/TCACP1634879.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x222e31d34c4a3b9b67ded5ec2dd9cde6e4f46600d1fe02d6c602e10fc9b235e3. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/TCAEH1985450.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x15b0054e87e634208f0bb8320fc50bb029448aadbb8a099896f16b7090295194. Chain 2 (Bitcoin): anchored in block 956349 (2026-07-02T11:34:59Z), 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/TCADZ1864238.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3e9ee5439b00baf41203e32e2cf9e46ffd7e19f0a74d60d542e18b683b99d629. Chain 2 (Bitcoin): anchored in block 960300 (2026-07-30T19:42:40Z), 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/QMEU32022966.
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 0x65ed8830b644e7c85381e4b46cb1ab6d16379f9e92a3db55ff8694bdf8f41518. Chain 2 (Bitcoin): anchored in block 960294 (2026-07-30T18:46:00Z), 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/QMEU32022964.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc9d008864e1070f54073c056ad2a45053e322f837e9611f3df40745b472e5434. Chain 2 (Bitcoin): anchored in block 960468 (2026-07-31T21:25:57Z), 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/QMEU32022971.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x57b816d73a963499925412d36f7f677fc7a14b7fb10492f739ea2c1a22b99681. Chain 2 (Bitcoin): anchored in block 960337 (2026-07-31T02:51:48Z), 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/QMEU32022973.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe21adb6063f5c976533d862694b1a2d34d215bf16b2acfcebd489528255d6c46. Chain 2 (Bitcoin): anchored in block 960448 (2026-07-31T18:48:12Z), 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/TCAEH1985428.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd41c333fe75c1fc20d38e4d3cceb99bfd4035b0ce4beaed45e82df68ba8a7554. Chain 2 (Bitcoin): anchored in block 960327 (2026-07-31T00:26:26Z), 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/TCAEH1985420.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8d3a5181e02788090d51c9da824c629ec16bed4c1fa5bf9eced8882c3157a517. Chain 2 (Bitcoin): anchored in block 960284 (2026-07-30T17:23:26Z), 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/TCADH1710113.