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 0x8d5b7157c28fc071bf2c00813bc36ee05ad0ed47d3945e1a525b433ea8b195f4. Chain 2 (Bitcoin): anchored in block 953939 (2026-06-16T11:40:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/20f8a459-e315-4158-8286-a8dd7af09351.json and https://artists.proofprofile.net/proofs/artist/20f8a459-e315-4158-8286-a8dd7af09351.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Two people's bookmark (feat. Ren Tsurumachi)
Transparent Spring (feat. Powa Yoshizawa)
wasurenatsu (feat. Poston.) [late summer arrange.]
勿忘夏 (feat. Poston.) [late summer arrange.]