Use Case
Blockchain Timestamps for Insurance Adjusters
Pre-loss documentation that holds up under adversarial scrutiny. How property and casualty adjusters, forensic engineers, and public adjusters use SHA-256 anchoring to establish tamper-evident evidence before incentives to fabricate exist.
The core problem with traditional pre-loss documentation
When a claim is disputed, the central question is often temporal: did this condition exist before the loss event, or was it caused by it? Traditional documentation — photographs, inspection reports, video — carries a credibility problem. Metadata can be altered. Dates can be forged. Files can be backdated. A shrewd opposing counsel will challenge any documentation that can't prove it wasn't created after the loss.
The standard response is to rely on third-party inspection services or certified inspectors. This adds cost, creates scheduling friction, and still depends on the inspector's record-keeping rather than a tamper-evident baseline tied to the document itself.
What blockchain anchoring does differently
A blockchain-anchored timestamp binds the timestamp to the exact bytes of the file — not to the envelope, not to the record system, not to the platform. The SHA-256 hash of the file is written to a public blockchain. Anyone can verify by hashing the same file and checking the on-chain record. Change one pixel of a photo, one word in a report — the hash doesn't match, and tampering is detectable.
Before the loss
- Anchor property inspection photos
- Anchor roof, HVAC, foundation documentation
- Anchor pre-existing damage assessments
- Record baseline inventory for high-value contents
When the claim arrives
- The on-chain timestamp proves files predated the loss
- Verification is public — anyone can confirm
- No dependency on ProofLedger's cooperation or continued operation
- Opposing counsel can verify with the
verify-proofPython package
Legal framework
Blockchain-anchored timestamps are authenticatable in US federal proceedings under FRE 901(b)(9), which allows authentication by "evidence describing a process or system that produces an accurate result." The process here is: SHA-256 hashing of the file, on-chain transaction recording the hash, and network consensus establishing the block timestamp. Each step is deterministic, testable, and independently verifiable.
Under the Daubert standard, the reliability factors — testability, peer review, known error rate, general acceptance — are satisfied by SHA-256 and public blockchain consensus, both of which have extensive peer-reviewed documentation in the cryptography literature.
The verification is adversarial by design. Opposing counsel doesn't need to trust ProofLedger. They hash the file themselves and check the Polygon or Bitcoin ledger directly. The record is public and permanent.
ProofLedger's dual-chain approach
ProofLedger anchors every proof simultaneously to two independent blockchains:
- Polygon — instant confirmation (typically under 30 seconds). High-volume workflows, routine pre-loss documentation.
- Bitcoin — daily Merkle batching. Bitcoin's proof-of-work chain has the deepest immutability and the highest recognition in US legal proceedings. The most persuasive chain for high-stakes litigation.
What ProofLedger does with your files
Nothing. The file never leaves the device that hashes it. Only the 64-character SHA-256 hash is transmitted to ProofLedger's servers and recorded on-chain. It is mathematically impossible to reconstruct the original file from its hash. This means ProofLedger is compatible with HIPAA-sensitive contents, attorney work product, and policyholder confidentiality requirements — because the file content never moves.
Who uses it
- Property and casualty adjusters — documenting property condition before catastrophic loss seasons (hurricane, wildfire) or during complex multi-cause claims.
- Public adjusters — representing policyholders whose pre-existing damage documentation is being challenged by the carrier.
- Forensic engineers — establishing chain of custody for site inspection data, especially when evidence collection is remote or contested.
- Risk managers — building tamper-evident baseline documentation for high-value commercial properties on an ongoing basis.
- Claims intake systems — API integration to anchor every uploaded document at the moment of ingestion, before it enters any internal system.
Pricing
The Baseline Access plan is free — 5 Polygon proofs lifetime, no credit card. For routine documentation workflows, Standard Evidence Access ($9.99/month) covers 100 Polygon proofs per month. For high-volume operations or litigation support with API integration, Formal Legal / Compliance ($99.99/month) provides unlimited Polygon proofs and REST API access. See full pricing →