The $0.20 CER Fire Sale: CDM Wind-Down Timelines, Legacy Supply Overhang, and Buyer Risk (Article 6 & CORSIA)

Why CDM credits are being dumped now: closure timelines, eligibility cutoffs, and policy uncertainty

Deadlines are forcing behaviour. The CDM Executive Board kept processing certain post-2020 items under temporary measures, but new submissions under those temporary measures stopped being accepted after 30 June 2023. That kind of cutoff does not just slow pipelines. It creates a rush to monetise whatever is already issued or close to issuance, because the operational path ahead becomes less predictable.

The CDM wind-down is also about utility, not climate physics. CERs were built for Kyoto-era compliance, and that compliance demand is largely gone. The Paris transition is incomplete, and the Article 6.4 mechanism is not a simple “CDM but renamed”. For many holders, the fear is straightforward: credits become stranded if they cannot be transferred, used, or credibly claimed under the rules buyers actually face.

Expiry dynamics add pressure. Many CDM activities used fixed crediting periods, and a significant share of those fixed periods had already run out by around 2022. That reduces the “fresh, easy-to-explain” part of the CDM supply, while leaving a very large legacy stock still sitting in accounts and inventories.

The scale of the legacy stock is the core overhang. The CDM has issued approximately 2,155,186,823 CERs in total, on the order of 2.1 billion units. When supply is that large relative to today’s realistic demand channels, price can collapse even if a minority of units are potentially usable.

Article 6 eligibility rules then turn oversupply into forced selling. Under the Article 6 carryover decision, only CERs from activities registered on or after 1 January 2013 can, subject to conditions, be used toward a Party’s first or first updated NDC. That single date makes many pre-2013 CERs close to commercially irrelevant for Paris-aligned uses, which is exactly when you see “get me out” pricing.

Policy uncertainty is the final accelerant. The treatment of CERs outside the defined eligibility is not something a buyer can diligence into certainty, because it depends on future CMA decisions. For a B2B buyer, that is pure regulatory risk: value is driven by what negotiators decide later, not by what the project did historically.

This is why the next question is not “are CERs cheap?”, but “who is exiting, who is buying, and what do they think they can do with them?”

Who is selling and who is buying: distressed holders, intermediaries, and opportunistic compliance strategies

Legacy holders are the natural sellers. Long-time developers, project SPVs, and traders who carried Kyoto inventory face ongoing costs, accounting complexity, and the risk that units become unusable. When liquidity matters, they sell in bulk lots, accept aggressive haircuts, and prioritise speed of execution over maximising price.

Intermediaries make the market tradable, but they also change the risk profile. Desks and brokers often aggregate mixed-quality lots across vintages, methodologies, host jurisdictions, and registry statuses. They then price a spread around the probability of successful registry transfer, the friction of settlement, and the risk that a buyer later discovers title issues. In practice, the secondary CER market is as much about registry transfer, title & encumbrances as it is about carbon.

Buyers tend to fall into three buckets. First are actors pursuing an NDC-first use case where CERs are allowed, typically focusing on 2013–2020 vintages and the procedural requirements that go with that. Second are speculative buyers who are effectively buying regulatory optionality, betting on future loosening. Third are corporates looking for “cheap offsets” who do not separate eligibility from claim integrity, which is where reputational risk spikes.

The opportunistic compliance angle is real, but it is easy to overestimate. Some buyers try to map CERs into internal accounting or anticipated schemes. In a post-Paris context, if corresponding adjustments and explicit acceptance are not in place for the intended use, “cheap” can quickly become “cannot be used” or “cannot be claimed”.

Procurement requests show what serious buyers actually filter for. An RFQ for “CERs eligible for first NDC” typically needs, at minimum: registration date on or after 1 January 2013, vintages pre-2021, unit type excluding tCERs and lCERs, and holdings positioned so transfer can occur under the applicable registry rules. It also needs process clarity on how transfer will be executed and how long settlement will take.

Once you see that demand is driven by options for use, the meaning of a $0.20 print becomes clearer. It is not automatically a bargain. It is a signal.

What $0.20 pricing really signals: oversupply, low utility, and the difference between price and value

A fire-sale price mostly reflects low utility, not low “abatement”. At very low levels, the market is pricing (i) limited regulatory usefulness, (ii) transaction-cost drag from diligence and settlement, and (iii) the risk that the unit cannot be used for a defensible claim. This is transaction-cost dominated pricing, with a thin layer of option value on top.

The overhang explains why clearing prices can approach zero. With roughly 2.1+ billion CERs issued historically, even a modest mismatch between what exists and what can realistically be used creates relentless downward pressure. In that environment, price is the probability-weighted value of future usability, not a measure of the underlying tonne.

For B2B buyers, price is not value. Value depends on your use case and your constraints: acceptance in a specific scheme, the ability to make a defensible claim, the vintage and status of the unit, host-country policy, and whether the unit can be aligned with Paris-era expectations around avoiding double claiming.

The “false economy” risk is practical, not theoretical. A buyer can pay $0.20 for a unit and then spend far more per CER equivalent on legal review, audit-style checks, KYC/AML, registry settlement work, and reputational remediation if the purchase becomes controversial. The all-in cost can exceed alternatives that looked more expensive on a headline basis.

Low-utility signals are usually visible early if you look for them. Common red flags include: pre-2013 registration; controversial project types for the buyer’s stakeholder context; incomplete documentation and issuance history; unclear chain-of-title; inability to transfer into the relevant registry pathway; and lack of host-country authorization where authorization is needed for the intended use.

If the price is mostly regulatory optionality, the next step is to map where that optionality is real. Article 6 and CORSIA are where many buyers look first, and where the barriers are highest.

Carryover into Article 6 and CORSIA: which CERs could still matter and where the barriers are highest

Article 6 carryover is narrow by design. CERs from activities registered on or after 1 January 2013 can, subject to conditions, be used toward a Party’s first or first updated NDC. That creates a higher-utility tier, but it is still a constrained pathway, not a blanket rehabilitation of the CDM.

Practical barriers matter more than theory. From a buyer perspective, the friction points are predictable: where the units are held and how they can be transferred under registry rules, whether host-country approval or authorization is required for the intended accounting treatment, exclusion of unit types like tCERs and lCERs, and the risk that additional requirements are introduced through future CMA decisions.

The CDM-to-Article 6.4 transition is a different track than CER carryover. Transitioning an activity into Article 6.4 is not the same as using existing CERs. Many activities will not be eligible, and others may require substantive realignment to new methodologies, baselines, and monitoring expectations. Buyers should treat “carryover units” and “transitioned activities” as two separate diligence workstreams with different failure modes.

CORSIA is often misunderstood in this context. CORSIA uses CORSIA Eligible Emissions Units from programmes approved by ICAO for specific periods, and CDM CERs are not automatically eligible. Aviation compliance procurement is therefore driven by the eligibility decisions and vintage windows of the approved programmes, not by the existence of legacy UN units.

Vintage windows make the mismatch obvious. For example, documentation for VCS under CORSIA sets requirements tied to emissions reductions occurring between 1 January 2021 and 31 December 2026. That kind of window highlights why legacy CERs typically do not solve CORSIA needs, even if they look cheap and plentiful.

If carryover is limited and CORSIA pushes buyers toward Paris-era units, the CER fire sale still matters. It can distort expectations and narratives well beyond the CDM.

Market impacts beyond the CDM: spillover risks for voluntary credit pricing, integrity narratives, and corporate claims

Very low CER prices can anchor negotiations elsewhere. When market participants see $0.20 headlines, it can create price anchoring in voluntary market discussions, especially for more commodity-like avoidance credits. That can pressure developers on forward offtake pricing and encourage a race to the bottom that is disconnected from the cost of producing high-integrity units.

The narrative spillover can be worse than the pricing spillover. “$0.20 carbon credits” is an easy talking point for critics, even though the drivers are specific to legacy Kyoto supply, eligibility cutoffs, and surplus. The result is often higher friction for everyone selling higher-integrity credits, because buyers demand more disclosure and more documentation to defend decisions internally.

Corporate claims are where cheap legacy units can become toxic. Using legacy CERs to support “carbon neutral” style marketing can be hard to defend under stakeholder scrutiny, particularly if the unit is not compatible with Paris-era expectations around avoiding double claiming and making credible claims. Procurement cannot treat this as a price-only decision, because legal and communications teams will inherit the downside.

Bundling creates contractual contamination risk. Intermediaries may bundle CERs with voluntary credits in a single commercial package, but the representations and warranties needed to make those units safe are not uniform. Mis-selling risk often shows up as ambiguity about eligibility, retirement mechanics, or what exactly the buyer is allowed to say after purchase.

Policy choices can also change buyer expectations across markets. If more Parties decide to use 2013–2020 CERs toward first NDCs, debates about ambition and perceived integrity can intensify. A predictable consequence is that buyers will more frequently demand host authorization and stronger double-claiming protections, even in voluntary transactions.

All of this pushes buyers and developers toward the same conclusion: the main job is avoiding stranded credits, not finding the lowest headline price.

Practical takeaways for international buyers and developers: due diligence, contract clauses, and how to avoid stranded credits

Eligibility has to be checked before price. Buyers should start by defining the intended use case, NDC-related use, a specific compliance scheme, or a voluntary claim, and then test minimum requirements: registration date on or after 1 January 2013 where relevant, the eligible vintage window, unit type excluding tCERs and lCERs, and the registry status plus the applicable transfer procedure.

Documentation should be treated like a settlement asset, not a nice-to-have. A B2B checklist typically includes the PDD, monitoring and verification records, issuance record, serial ranges, chain-of-title evidence, attestations that units are free of liens or encumbrances, KYC/AML on the seller, and proof of the right to transfer or retire in the relevant registry pathway.

Contracts should be written to prevent stranding, not to assign blame after the fact. Common protections include: conditions precedent tied to successful transferability into the designated registry account, explicit eligibility and usage representations referencing the scheme and period, clear remedies such as replacement units, unwind, or price adjustment, a long-stop settlement date, and indemnities covering double sale, double claiming, and title defects.

Pricing should be modelled as an option with costs attached. Treat legacy CERs as probability times payoff, and separate the commodity price from diligence, legal, registry, and reputational costs. The decision metric that matters is the all-in cost per tCO2e that is actually usable and claimable for your defined purpose.

Developers holding inventory should segment early and communicate clearly. Units that are potentially eligible for first NDC use should be packaged with a clean data room and a realistic transfer path. Units that are not eligible should be handled in ways that do not create downstream misrepresentation risk, including considering non-offset framing such as climate contribution or cancellation where appropriate.

The best protection is not buying low. The best protection is buying units that are usable and defensible, backed by contracts that allocate the risk of future CMA decisions and programme restrictions to the party best able to manage it.