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Lawyers & Notaries

From paper trail
to cryptographic provenance.

PV asset transactions require establishing what was installed, who owns it, and what changed — from commissioning to the present day. DERpass provides a hash-chained revision history, content-referenced documents, and optional JWS signatures that reduce chain-of-title work from weeks to hours.

What legal professionals deal with today.

01

Weeks to establish chain of title

Proving ownership history for a PV asset requires collecting scanned contracts from multiple parties, cross-referencing installer invoices with grid approval letters, and verifying dates against disconnected records.

02

Documents scattered across parties

The installation contract is with the installer. The grid approval is with the DSO. The insurance policy is with the owner. The maintenance contract is with the O&M provider. None of them use a consistent format.

03

No standard way to prove what changed

If an inverter was replaced, a battery added, or an ownership transfer completed, there is no standard mechanism to record this in a way that can be verified by a third party without contacting each involved party.

04

Certified copies required for each transaction

Real estate transactions involving PV assets require certified copies of installer certificates, grid connection approvals, and insurance policies — collected anew for each transaction, even when they have not changed.

What legal professionals need from a data standard.

R1

Verifiable chain of ownership

Every ownership transfer should be recorded in a structured, timestamped entry that links the previous and new owner, the date of transfer, and the relevant document — without relying on any central registry.

R2

Document references with integrity hashes

Contracts, insurance policies, and approvals should be referenced in the asset record with cryptographic hashes — so that the existence and integrity of the document can be verified without requiring the original to be re-submitted.

R3

Tamper-evident revision history

The record of what changed and when should be structured so that any alteration — adding, removing, or backdating an entry — is detectable by any party holding a prior version of the file.

R4

Authorship proof without a central notary

Parties should be able to prove that they authored or approved a specific event — a commissioning, an ownership transfer, a component replacement — without relying on a central certification authority.

How DERpass addresses these needs.

Hash-chained revision history

The revisions chapter records every file version with a SHA-256 content hash, the date, the responsible party, and a reason. Each revision references the hash of the previous one — forming a chain where any alteration breaks the link and is immediately detectable.

Documents referenced with content hashes

The documents chapter lists every associated document — installation contract, grid approval, insurance policy, O&M agreement — with a title, date, and SHA-256 hash. The hash proves the document existed and has not changed, without requiring it to be re-submitted.

Structured ownership events in the event log

Ownership transfers are recorded as typed events in the events chapter: date, previous owner, new owner, document reference, and optional JWS signature from the notary or both parties. A complete ownership chain from commissioning to present is visible in a single file.

JWS signatures prove authorship without a central authority

Any event in the log can carry a JSON Web Signature from the party responsible — the installer at commissioning, the notary at transfer, the O&M provider at handover. The public key verifies the signature; no central registry or certification authority is required.

Who this applies to.

Becker Büttner HeldEnergy Law · DE
CMS Hasche SigleEnergy & Real Estate Law · DE
Görg PartnerschaftCorporate & Asset Law · DE
Notare & NotariateProperty Notaries · DE/NL
Allen & Overy AmsterdamRenewables Finance · NL
Real Estate SolicitorsProperty transactions with PV

Relevant use cases. The inheritance and system sale use cases show how a DER Passport travels through an ownership change — with the revision history, ownership event, and document references already in place.