A spearhead is the sharpened point (head) of a spear, similar to an arrowhead. It is often a separate piece called a projectile point. Spearhead may also refer to: Armed conflict Armoured spearhe
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 0x6cdf48f44e9b4946842b108f7f2d8e8377e6254631bc285e82142981b7cc6d92. Chain 2 (Bitcoin): anchored in block 953807 (2026-06-15T16:39:18Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/f1f34ead-6ee4-4ba5-8778-e6abb5a1a424.json and https://artists.proofprofile.net/proofs/artist/f1f34ead-6ee4-4ba5-8778-e6abb5a1a424.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Jan Douwe Kroeske presents: The Best of 2 Meter Sessions 1987-2009
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 0xbf054e95938dfd36839a69f04ef2163efb2a530087fb4e3afc985303f6814c7a. Chain 2 (Bitcoin): anchored in block 957067 (2026-07-07T16:54:37Z), 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/NL07C2061818.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfcb6fd2a79a1be61f9e408b28a1c0893e0685d04234a801cb53b40fc04923541. 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/USCA29400237.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcba945a48fdf5fab500d970074fe3edae0f27ab9dcfcd4aa62d51e4329fc0963. 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/USCA29400302.
Jan Douwe Kroeske presents: 2 Meter Sessions, Vol. 9
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb102a4c3ad511d337bcb840c2c310847ae59eab2ea9792275722ce81cdd84188. 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/NL07C1700471.