Der or DER may refer to: Places Darkənd, Azerbaijan Dearborn (Amtrak station) (station code), in Michigan, US Der (Sumer), an ancient city located in modern-day Iraq d'Entrecasteaux Ridge, an oce
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 0x7ac2b92b140f609d37bdc12cb9ab8a4464241641e34803b4e2df2ba49f706d70. Chain 2 (Bitcoin): anchored in block 954580 (2026-06-20T17:48:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b7504487-286d-43c6-9b7d-7fd0d087a327.json and https://artists.proofprofile.net/proofs/artist/b7504487-286d-43c6-9b7d-7fd0d087a327.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).