The method this registry runs on, published as a numbered document, so that a reviewer can check a claim against a version rather than against a website. Version 1.0, 2026-11-06, CC BY 4.0.
Author: Wong, Erik C. · ORCID 0009-0004-6360-4415 · ZeroCarbon Verify (HK) Limited (in incorporation) · contact erik.cywong@live.com
DOI: 10.5281/zenodo.24015356 — published on Zenodo, Archived at Zenodo (v1.0). The deposited PDF, the register snapshot and the verifier are downloadable from both places and are byte-identical.
| File | What it is | Size |
|---|---|---|
| CJV-MTH-1.0.pdf | The specification, 12 pages, 22 sections, 18 tables | 244 KB |
| register-labels.json | The register snapshot the document describes — 20 records, head 54980f3d |
26 KB |
| verify_register.py | Dependency-free verifier: recomputes payloads, chain, arithmetic and grades | 3 KB |
Deposited on Zenodo under DOI 10.5281/zenodo.24015356. The DOI is quoted here and on the establishment file next to the method hash, so that a citation can be checked against a version rather than a page.
| Section | Content |
|---|---|
| 6 | The verified unit: five properties, eighteen required fields, invariants that must reject at issuance |
| 7 | Evidence grading: the grade is arithmetic over the metered share, never commercial preference |
| 8 | Counterfactual baseline: it must be co-signed before the improvement it measures |
| 9 | Refusal semantics: four classes, recorded with the same care as a unit |
| 10 | Canonical payload, FNV-1a parameters, chain construction, revocation |
| 12 | The claim partition: what an evidence layer may state, and what needs a countersignature |
| 13 | Conformance test vectors taken from the live register |
| Property | Requirement | Fails when |
|---|---|---|
| Metered | The footprint derives from measured quantities | Only invoices exist |
| Bounded | Boundary and functional unit fixed before data collection | Chosen after the result |
| Attributed | One owner, one location, one batch id | Split across sites without a rule |
| Committed | Hashed at issuance, not editable afterwards | A value is revised silently |
| Recomputable | A third party reproduces the hash without the issuer | Verification requires asking us |
A record failing one property is not a weaker unit. It is not a unit.
Download the two files above and run the verifier. It needs no dependencies beyond Python 3.8 and no network access; it recomputes every hash from the published fields.
python verify_register.py
file: register-labels.json
records: 20
declared head: 54980f3d
recomputed head: 54980f3d
method: CJV-MTH-1.0 / 9b12abef
OK — payload, chain, arithmetic and grades all verifyChange one digit in the snapshot and the run fails, naming the first record that breaks and every record after it. That is the whole point: a claim that cannot be checked by someone who does not trust us is not evidence.
| # | prev | payload | hash |
|---|---|---|---|
| 1 | genesis | AP-8885|185.735|0.307|A | 889fdaf6 |
| 2 | 889fdaf6 | AP-2856|295.75|0.338|B | f24da836 |
| 20 | f0238400 | AP-7315|224.406|0.273|A | 54980f3d |
| Not this | Why |
|---|---|
| An accredited standard | No accreditation body has assessed this body; conformance is a statement about structure, not competence |
| A certification | The specification defines records; conclusions are countersigned by a licensed partner |
| Evidence of effectiveness | It contains no pilot and no evaluation — Section 15 says so |
| A cryptographic guarantee | FNV-1a resists casual modification, not an adversary who rewrites the whole chain |
Wong, Erik C. (ZeroCarbon Verify (HK)). CJV-MTH-1.0 — Evidence-Graded Product Carbon Claim Registry: Specification, version 1.0, 2026. ORCID 0009-0004-6360-4415. DOI: 10.5281/zenodo.24015356.
When citing the register, quote the record count and head hash alongside the date — the register changes, the citation should name the state it referred to.