Third-party verification, inside the platform.
Independent verifiers review your carbon claims in a dedicated workspace, raise findings against the data, and issue a formal opinion — no email chase.
- Global verifiers connected
- Most comments resolved in round one
CarbonSig verification workspace at carbonsig.app. An illustrative steel billet product carbon footprint has completed third-party review. Its three nodes — Iron ore (input, Scope 3), Blast furnace (process) and Steel billet (output, 1.9 kg CO₂e per kg, ISO 14067) — are all reviewed. Zero findings open, one resolved in round two. Verification lifecycle: Self attested, Pending, Under verification, Revisions, and now Verified on CarbonSig.
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How does verification work on CarbonSig?
On CarbonSig, third-party verification happens inside the platform. An independent, accredited verifier gets a read-only Verifier Hub tied to your registered model, raises findings pinned to the exact node, and works round by round to a formal opinion — “Verified on CarbonSig.” CarbonSig hosts the workspace; it does not verify. The verifier is independent.
Verification, chased through consultants and inboxes.
The old way
On CarbonSig
Same platform for both packages: Enterprise platform or White-glove service.
Consultants & inboxes
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Findings scattered across email threads
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Rebuild the model from scratch each round
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An untraceable number you can't defend
One connected platform
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Findings pinned to the exact node
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A locked snapshot per round
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Node-by-node review, claim to opinion
From self-attested to Verified on CarbonSig.
The verifier accepts the engagement
A read-only review environment opens on your registered snapshot.
Findings are raised in context
Each one pinned to its Model → Product → Node path. 5–15 findings in a first review is normal.
You resolve them round by round
Each round is a locked snapshot, so there’s an immutable audit trail from claim to opinion.
The verifier issues a formal opinion
The engagement completes and your products read “Verified on CarbonSig.”
See exactly what a verifier sees — node by node.
The verifier works in a read-only copy of your registered model. Findings are pinned to the exact node. Each round is a locked snapshot. The result is an immutable trail from the first claim to the final opinion — the audit story told once, in order.
CarbonSig verification workspace at carbonsig.app. An illustrative steel billet product carbon footprint is under third-party review — round 2, revisions requested. The system model has five nodes: Iron ore (input, Scope 3, reviewed); Grid electricity (input, Scope 2, reviewed); Blast furnace (process, draft); Direct emissions (Scope 1, draft); and Steel billet (output, reviewed, 1.9 kg CO₂e per kg, ISO 14067). One finding, pinned to Grid electricity, has been resolved in round two: requirement ISO 14067 data quality — the client attached meter data and added a reference. Zero findings open, one resolved. Verification lifecycle: Self attested, Pending verification, Under verification, Revisions requested (current), Verified on CarbonSig. Verification partner: Bureau Veritas. Implementation partner: Kabyax.
In partnership with
Verification partner: Bureau Veritas — co-developer of the verification module.
Implementation partner: Kabyax
Built to the standards your verifier already uses.
ISO 14064-3
Aligned with the standard for verification and validation of GHG assertions; Sankey supports risk-based sampling.
ISO 14067
Aligned with the product carbon footprint standard your claim is calculated to.
GHG Protocol Product Standard
Aligned with the product-level accounting your verifier expects.
A governed workspace for the work you already do.
Accept the engagement
Your own verifier account and a central Engagements workspace; open one for a read-only review environment (Explore · Analyze · Sankey · Bar Chart).
System › Process › Grid electricity
+ FindingReview in context
Raise a Finding and the traceability path (system / process / node) is pre-filled for you; Properties, Requirements and Findings stay in view.
Issue your opinion
Round-based revisions with locked snapshots, through to a formal opinion recorded as “Verified on CarbonSig.”
A person will reply within one business day.
Co-developed with Bureau Veritas.
Bureau Veritas — verification partner; co-developer of the verification module.
“The structured data export eliminated the usual back-and-forth. We could focus on assurance, not archaeology.”
“When a client arrives with a CarbonSig package, we know the evidence is there, organised, and has been through a readiness check.”
A verified number becomes a Carbon Receipt.
When the opinion is issued, your product carries a CAP — a Carbon Attested Product. It’s a live, shareable record, not a static PDF: 628 variables verified in each CAP, 5+ standards mapped per attestation.
CBAM acceptance
A verified number your EU importer can file, instead of a punitive default.
A higher 45V tier
A verified hydrogen carbon intensity drives the credit, up to $3.00/kg.
Green financing & premium markets
Verified low-carbon steel commands 20–30% premiums in Europe (green premium €50–300/t).
What clients ask before verifying.
What does verification cost?
Independent third-party verification runs, as industry estimates: simple $3,000–$8,000, standard $8,000–$18,000, complex $15,000–$35,000, enterprise $30,000–$80,000+. These are estimates — scope, standard and the verifier set the final fee. No third-party consultant needed; you still need an independent verifier.
Simple
$3,000–$8,000
Standard
$8,000–$18,000
Complex
$15,000–$35,000
Enterprise
$30,000–$80,000+
Industry estimates for the independent verifier’s fees — not a CarbonSig price. Independent verifier required separately. Costs vary by project scope.
How long does it take?
Third-party verification typically takes 8–20 weeks end to end. Roughly: prepare your data 4–12 weeks, select a verifier 1–2, the review itself 2–4, resolve findings 1–3, and the formal statement about 1 week. CarbonSig hosts the review round by round; the independent verifier sets the pace.
Industry estimate; the independent verifier sets the pace. Independent verifier required separately. Costs vary by project scope.
What is a finding?
A finding is a verifier-raised issue in a review round, pinned to a specific node by its Model → Product → Node path, and tracked open → resolved round by round until the verifier issues an opinion. Findings are expected, not failure: 5–15 findings in an initial verification is completely normal.
Can you verify for 45V?
For 45V, you model and register the hydrogen or ammonia carbon intensity (kg CO₂e/kg H₂) and route it through independent third-party verification on-platform — a verifiable pathway. The verified intensity drives the credit tier, up to $3.00/kg. Facilities placed in service after January 2028 no longer qualify. Real example: a US DOE 45V ammonia analysis. See the 45V solution page.
Client or verifier — let's get your numbers verified.
We'll show you the workspace that ends the email chase, for the client with the number and the verifier signing it off.
Independent verifier required separately. Costs vary by project scope.