Carbon-market buyers are increasingly looking to Article 6 of the Paris Agreement as a potential route to stronger integrity and clearer international accounting.
That interest is understandable. Article 6 provides a framework through which countries can cooperate voluntarily in achieving their climate targets. Article 6.4, also known as the Paris Agreement Crediting Mechanism, is designed to support verifiable emissions reductions and removals, mobilise finance and facilitate international cooperation.
But a critical point is often lost in the market conversation: Article 6 is not a shorthand for “high quality”.
A credit’s credibility depends on the full chain of evidence behind it—how the underlying emissions outcome was quantified, whether it is additional, how reversals and leakage are managed, who has authorised its use, what accounting treatment applies, and what claim the buyer intends to make.
For buyers, investors and boards, the right approach is to treat Article 6 credits as a diligence-intensive asset class rather than a marketing category.
Five questions every buyer should ask
1. What exactly has been authorised—and by whom?
The first question is not whether a project is “Article 6 aligned”. It is whether the relevant host country has issued a specific authorisation, what use has been authorised and whether the authorisation is clear, current and verifiable.
Under the Article 6.4 mechanism, the host Party specifies whether it authorises Article 6.4 emission reductions for use towards its nationally determined contribution (NDC) and/or for other international mitigation purposes. Buyers should therefore seek the underlying host-country documentation rather than rely solely on a project summary or intermediary statement.
The intended use matters. A mitigation outcome authorised for use towards another country’s climate target may have different accounting and claims implications from one considered for another international mitigation purpose.
2. Will a corresponding adjustment apply?
A corresponding adjustment is central to avoiding double counting when an emissions reduction is transferred internationally for certain uses. It is an accounting mechanism applied by governments—not a feature a corporate buyer can create through contractual wording.
The UNFCCC’s Article 6.2 guidance explains that corresponding adjustments apply to internationally transferred mitigation outcomes and are intended to support transparency, accuracy, completeness, comparability and consistency in international accounting.
The buyer should understand the relevant national rules, the status of the adjustment and how the transaction is reflected in the host country’s emissions accounting. Where clarity is absent, companies should avoid claims that imply exclusive ownership of a national mitigation outcome.
3. Does the project stand up without the Article 6 narrative?
Article 6 does not replace core carbon-credit integrity tests.
Buyers should still assess baseline setting, additionality, permanence, leakage, robust quantification, monitoring, independent validation and verification, safeguards and grievance mechanisms. The Integrity Council for the Voluntary Carbon Market’s Core Carbon Principles offer a useful due-diligence benchmark, covering governance, tracking, transparency, additionality, permanence, robust quantification, no double counting and sustainable-development safeguards.
A strong legal structure cannot rescue weak underlying climate impact. Equally, a technically robust project may still carry material delivery risk if host-country approvals, registry processes or international transfer procedures are incomplete.
4. What claim will the company make?
The credit should be purchased for a defined purpose.
Is it intended to provide climate finance beyond the company’s value chain? To support a host country’s transition? To address residual emissions under a clearly stated policy? Or to support a product or customer proposition?
The claim must match the credit’s attributes and the company’s own decarbonisation strategy. Buying credits should not become a substitute for reducing operational and value-chain emissions.
The Voluntary Carbon Markets Integrity Initiative’s Claims Code provides a useful reference point: credible claims should sit alongside robust corporate climate action and should be supported by high-integrity credits.
A credible climate strategy puts direct emissions reductions first, then explains transparently why—and how—carbon finance is being used.
5. Who carries delivery and reversal risk?
Article 6 transactions may involve more counterparties, approvals and timing dependencies than conventional voluntary credits.
Contracts should address issuance risk, authorisation withdrawal or amendment, delays, invalidation, reversal events, replacement obligations, registry fees, change-in-law events and dispute resolution. The UNFCCC’s Article 6.2 reference material notes that authorisations can be changed, with revisions submitted through the Article 6 reporting process.
The commercial value of a carbon credit is therefore inseparable from its legal, accounting and contractual attributes.
Article 6 can help channel capital towards credible climate action and improve alignment between international transfers and national climate goals. But disciplined buyers will not ask simply, “Is this Article 6?”
They will ask: What precisely are we buying, what can we credibly claim, and what evidence supports it?
That is the difference between buying a carbon-market product and making a defensible climate-finance decision.