# My buyer wants a third-party verified carbon footprint. What does that involve for a small supplier?

Canonical: https://senseible.earth/answers/buyer-asks-third-party-verified-footprint

First build a documented inventory or product footprint, then hire an accredited body to verify it: ISO 14064-3 for a company inventory, or a critical review or verification for an ISO 14067 product footprint. Verifiers sample invoices, so records matter more than reports.

## Order of work

1. Agree with the buyer: company inventory or product footprint, and which year.
2. Collect fuel, electricity and production records for that period.
3. Prepare the calculation with factors and sources.
4. Engage a verifier and answer their sample requests.

## Ask first

Some buyers accept a documented calculation for the first year. Check before paying for verification.

## What Senseible does here

Senseible reads fuel, electricity and production documents into dated, fingerprinted plant records, so the monthly intensity behind a compliance figure can be traced to its source.

- [Is ISO 14067 mandatory?](https://senseible.earth/answers/is-iso-14067-certification-mandatory)
- [How many invoices a verifier samples](https://senseible.earth/answers/how-many-invoices-does-a-verifier-sample)
- [Estimation note for a verifier](https://senseible.earth/answers/estimation-note-for-verifier)

Sources: [ISO 14064-3 and ISO 14067 (iso.org)](https://www.iso.org), [GHG Protocol Corporate Standard](https://ghgprotocol.org/corporate-standard)

Last reviewed 2026-10-22.