David Friesen (born May 6, 1942) is an American jazz bassist. He plays double bass and electric upright bass.Scott Yanow, [ David Friesen] at AllMusic Career thumb|left|David Friesen at Bach Dancin
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 0x0c6a915328d107707552fe12cb9b66202c18e9cc7053ba2b8f41119d78a4ef44. Chain 2 (Bitcoin): anchored in block 953907 (2026-06-16T07:39:24Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/17838f2b-93ac-4f65-9569-e0ae1c5328e0.json and https://artists.proofprofile.net/proofs/artist/17838f2b-93ac-4f65-9569-e0ae1c5328e0.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Four to Go (feat. John Gross, Gary Barone, Alan Jones)
Friesen, David / Kropinski, Uwe: Made in Berlin
Friesen, David / Kropinski, Uwe: Made in Stanbul
Friesen, David / Kropinski, Uwe: Made with Friends
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 0x2460b64f666797773324fa96a7e717d2e619bbcd609b173303b59580f1e89bef. 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/USB8U1067842.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa3f9ea31e38c6225493e7226f5379b899d9626976a49a05c7b3278cbbd3a6778. 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/USB8U1067846.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xab7623a24abfb9ec751af3cb31f48e6b4e27d0441a45a922c617eca89d19f764. Chain 2 (Bitcoin): anchored in block 960418 (2026-07-31T15:20:15Z), 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/USB8U1067841.
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 0x289fd7cdd9d1ea2f2c720ba46463c10bb487447ade263992a0d4ca495cbdfb96. Chain 2 (Bitcoin): anchored in block 960455 (2026-07-31T19:53:13Z), 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/USB8U1067843.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4708751d6fb311bae42f06f06068af76a614800decc7b79fcf8fe1d6972a0d71. Chain 2 (Bitcoin): anchored in block 960410 (2026-07-31T13:50:38Z), 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/USB8U1067845.