Eric Halfvarson (born December 1, 1951, in Aurora, Illinois) is an American operatic bass. He made his professional debut in 1973 with the Lake George Opera (now the Opera Saratoga) as Don Basilio in
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 0xa01acae19ae425f2a6b0cad7d6484207303a3c71c9f82627d406561a9e3435d6. Chain 2 (Bitcoin): anchored in block 954008 (2026-06-16T21:31:27Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/33543b4f-3bab-450e-b64c-961e4320aea9.json and https://artists.proofprofile.net/proofs/artist/33543b4f-3bab-450e-b64c-961e4320aea9.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 0x0f5f3e3a75c841610e9ac2748c83f35cb185bdcd9f406c3a7cecaf43d85c5f15. 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/GBLWD0414101.
The flying Dutchman, Scene 2: Yohohoey! I see a ship, as black as night (Senta, Girls, Mary)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc57e3049594cd5bb0922f678b58ba7fa9744a5bb3f0fd4ed2d42e18c892c2b07. Chain 2 (Bitcoin): anchored in block 960236 (2026-07-30T09:37:10Z), 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/GBLWD0414201.
The flying Dutchman, Scene 1: Hoyohey! Halloyo! Ho! Hey! (Sailors, Daland, Steersman)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3cc0c0b6160b7edd508a67b0fd81f7fba7ccf365ab17299c0c1398625547416e. 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/GBLWD0414102.
The flying Dutchman, Scene 2: Stay, Senta! Stay awhile and talk with me (Erik, Senta)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x92c4f165b70193be3214ee0cb12d95a5cba777087a5d7f70dafe3b9935c41891. 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/GBLWD0414202.
The flying Dutchman, Scene 1: The time has come (Dutchman, Dutchman's Crew)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2e609a2e2e73a945dafa34663235d9078867faeb3ed01f5f4912648258e83083. Chain 2 (Bitcoin): anchored in block 957073 (2026-07-07T18:39:05Z), 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/GBLWD0414103.
The flying Dutchman, Scene 2: My child, your father's on the threshold (Daland, Senta)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd5444b6a0e36a563e1586d593068d46d43bbf869ab693542f99f0fc3c39dd824. 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/GBLWD0414203.
The flying Dutchman, Scene 1: Hey! Holla! Steersman! (Daland, Steersman, Dutchman, Sailors)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbf79e47af53ecc901f2082f904f6ae278bd5a751102d87af92843bd5e399d321. Chain 2 (Bitcoin): anchored in block 960193 (2026-07-30T02:05:19Z), 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/GBLWD0414104.
The flying Dutchman, Scene 2: Senta, my child, extend a welcome to this stranger (Daland)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2a37b07ff2fd89dd90deee8cd245a3714912f8db3e24376015cbb01c2e1715a7. 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/GBLWD0414204.
The flying Dutchman, Scene 2: Whirr and whirl as morning passes (Girls, Mary, Senta)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x55ffcdcc5cde2da0b270b3f9aa8b4d0104a684a9910682a0fb955d915862f835. 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/GBLWD0414105.
The flying Dutchman, Scene 2: As from the distant dawn of my creation (Dutchman, Senta)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7949c8a9dda838b131fcc56eedf97260647514d4a2a296e4572d34afca760bc3. 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/GBLWD0414205.
The flying Dutchman, Scene 2: My crew are bored with this delay (Daland, Senta, Dutchman)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x68eeb828594bb96327648bfe5c68aa10fb939d7178df4ecb4325f7d5b1d44a55. Chain 2 (Bitcoin): anchored in block 960348 (2026-07-31T05:17:02Z), 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/GBLWD0414206.
The flying Dutchman, Scene 3: Steersman, leave your watch! (Norwegian Sailors, Girls, Steersman, Dutchman's Crew)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe032425c835abe5556b6673723116b53fd03b0a0e3d8114636a29811dc1f6c1a. 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/GBLWD0414207.
The flying Dutchman, Scene 3: What is this madness? (Erik, Senta)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d5cfd0f75fdafdd948ea15e529b77d03514d8b2ceea509bec8f3b9700186f25. Chain 2 (Bitcoin): anchored in block 960362 (2026-07-31T06:58:00Z), 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/GBLWD0414208.
The flying Dutchman, Scene 3: Could you forget those carefree happy hours (Erik)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x646b89f9a4d56f8b022294ba18d7a4c5896bae991c594e0f10fbc9c8977aa0c4. 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/GBLWD0414209.
The flying Dutchman, Scene 3: It's hopeless! Ah! It's hopeless! (Dutchman, Erik, Senta, Daland, Mary, Girls, Sailors, Dutchman's C
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa11505be5e2a78f4c567d4bc7da0a6deaf71a7d7c9e91948b2f7f466675d8470. 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/GBLWD0414210.
Rigoletto / Act III: "Ah, più non ragiono!..." - Live At Metropolitan Opera House, New York / 2011
Anna Netrebko - Live at the Metropolitan Opera
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x16cab1e93cae837cbabc7e3145afd333eadffe64ad567739e5aa27bbf91eac2d. Chain 2 (Bitcoin): anchored in block 960254 (2026-07-30T12:06:10Z), 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/DEUM71102725.