How Oka and DelAgua pioneered the CORSIA insurance market

Introduction

In 2024, the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) entered its First Phase, creating the first global compliance demand signal for eligible voluntary carbon credits. But supply could not yet move at scale. Registries, developers, and buyers still needed a workable solution for managing the double-claiming risk that faces credits authorised but not yet accounted for.

That unresolved risk sat at the centre of the International Civil Aviation Organization (ICAO) Technical Advisory Body’s approval process. Verra and Gold Standard, the two largest voluntary carbon registries, were approved to issue CORSIA-eligible emissions units (EEUs) on the condition they demonstrate how double-counting risk would be managed.

Oka had recently partnered with cookstove developer DelAgua to tackle the same problem in practice. In October 2023, DelAgua secured a signed Letter of Authorisation (LoA) from the Rwanda Environment Management Authority, giving it one of the earliest pools of Article 6-authorised voluntary carbon credits with a route to CORSIA.

The opportunity was significant: a constrained market needed eligible units, and DelAgua was uniquely positioned to supply them. But before those credits could move at scale, buyers and registries needed a mechanism to manage the residual risk of LoA withdrawal or corresponding adjustment failure.

DelAgua had worked closely with the Rwandan government for 12 years and expected the adjustment to be applied. For airline operators and intermediaries, however, trust in the host-country process was not enough. They needed assurance that affected credits could be replaced and compliance claims protected if the authorisation failed.

DelAgua approached Oka to design an insurance solution for that gap. The result was Oka’s Corresponding Adjustment Protect, a first-of-its-kind policy designed to protect against revocation and give airlines the security needed to transact with confidence. The product helped create a live commercial precedent that registries could point to as they formalised insurance-backed CORSIA pathways.

Overview

Client: DelAgua

Carbon vertical: Clean cooking

Projects: Rwanda, Sierra Leone, The Gambia

Insurance policy: Corresponding Adjustment Protect

Risk(s) covered: Letter of authorisation revocation or corresponding adjustment failure

Role of Oka: Product design, underwriting, policy placement, registry-market engagement, and implementation support

DelAgua is a leading clean cookstove project developer working across rural Sub-Saharan Africa. Its Live Well programme has distributed over 2 million stoves, transforming more than 9 million lives, reducing reliance on firewood, and supporting lower-emission household energy use. Its programme reduces wood use by 71%, has prevented more than 14 million tonnes of CO₂, and has created over 10,000 project-based work opportunities.

The commercial opportunity was specific. DelAgua had secured an early LoA, but at the time, no large voluntary registry had a TAB-approved route for managing the double-counting risk that came with it. That pathway had to exist before the credits could be sold into CORSIA.

Objective

Driving the Oka-DelAgua collaboration were three objectives:

1. Resolve the double-counting condition holding back CORSIA supply. Build a commercially viable insurance route that protects buyers and that registries and the TAB could recognise as a credible safeguard.
2. Give DelAgua first-mover commercial advantage. Help DelAgua convert the first signed LoA into buyer-ready CORSIA supply, reduce sales friction, and reassure airline buyers entering a new compliance market.
3. Connect market infrastructure to real-world impact. Support demand for credits generated by clean cooking projects, where carbon revenue helps fund household-level climate, health, and economic outcomes.

Strategy

1. Identify insurance as the answer to the TAB's double-counting condition

When Oka began this work in early 2024, the structural problem inhibiting CORSIA supply was clear. The TAB had asked Verra, Gold Standard and other major programmes to demonstrate how they would manage the risk of host-country reneging on corresponding adjustments: a risk that, left unaddressed, would either expose project developers to unbounded replacement liability or leave buyers with no remedy if credits lost eligibility post-sale.

Oka's product team reviewed the TAB's recommendations and the registry submissions to date. Just one registry had been formally approved. Buried in its submission was a reference that had not been cited in any other: insurance as a lever for managing double-claiming risk.

In practice, insurance became the scalable commercial route for resolving the condition before corresponding adjustments had been completed. Standards-level safeguards alone could not compensate a buyer if a corresponding adjustment failed years after transaction and even retirement. Insurance could.

That diagnosis became the basis for the work that followed. Oka engaged with registries and market participants to develop a market design showing how an insurance policy could sit alongside LoAs, registry safeguards and corresponding adjustment processes, and how it could satisfy the TAB’s double-counting safeguard.

2. Build the first CORSIA insurance policy, backed by Lloyd's capacity

Identifying the mechanism was one thing. Pricing and binding a policy for a risk that had no historical loss data was another. Oka built the underwriting approach around project- and country-specific analysis, working closely with DelAgua and the Government of Rwanda. The policy provided multi-year cover, carrying the risk from LoA issuance to Biennial Transparency Report (BTR) submission. Having reviewed the project and LoA, Oka was able to provide a quote.

What is a Biennial Transparency Report (BTR)?

The policy was underwritten by Oka Syndicate 1922 at Lloyd's. That mattered because buyer concern was not just technical. Airlines and intermediaries would need a mechanism backed by recognised insurance capacity. Lloyd's capacity made it credible.

The first commercial Article 6 insurance product brought to market, Corresponding Adjustment Protect closed the gap between insurance as a theoretical mitigation and insurance as a transactable instrument.

3. Create the first live proof point with DelAgua, catalyse market activity

DelAgua was the first developer to bind a CORSIA insurance policy. The June 2024 placement demonstrated that the pathway Oka had architectured could be priced, underwritten, and transacted. DelAgua, meanwhile, reported that the policy was used on its biggest transaction to date and had helped push the sale over the line.

That precedent mattered for three reasons. It gave airline buyers and intermediaries a working example of how insurance could resolve their double-counting concerns; it signalled to developers that the opportunity was accessible and significant; and it gave registries a reference point as they finalised their CORSIA pathways: an existing, Lloyd's-backed product already in market.

4. Set the precedent for registry frameworks, grow the insurance market

Oka's product was in market a full year before the major global registries finalised their formal insurance frameworks. In the intervening months, we worked with Verra and Gold Standard to incorporate insurance into their resubmissions. Gold Standard received full ICAO approval in December 2024. In July 2025, it launched a formal assessment process for third-party insurance policies, appointing Howden Group as the advisor. Verra finalised its own insurance framework in the same window.

In late 2025, Gold Standard formally approved Corresponding Adjustment Protect as an Approved Insurance Policy, alongside one other private policy and the Multilateral Investment Guarantee Agency (MIGA)’s breach of contract cover. Verra would follow soon after, with DelAgua bringing to market the first CORSIA-eligible, Verra-tagged credits in early 2026.

The sequence is important. Oka identified insurance as the mechanism, designed the first commercial product, and bound the first live policy in 2024. Following Howden’s appointment as a registry-side adviser in mid-2025, other insurers entered the category, building on and bringing much-needed capacity to the route that Oka was proud to pioneer.

Outcomes

1. Commercial outcomes

• First-mover advantage: DelAgua converted its LoA into buyer-ready supply, becoming the first developer to bring Verra-issued insurance-backed credits to market in 2026.
• Commercial support: In 2024, DelAgua reported that the policy was used on its "biggest sale to date" and helped "push the sale over the line.”
• Market validation: DelAgua has since announced 4,776,194 credits from projects in Rwanda, The Gambia, and Sierra Leone have received eligibility tags.
• First retirements: In March 2026, the first CORSIA-tagged DelAgua credits backed by Corresponding Adjustment Protect were retired by airline buyers, closing the loop from authorisation-via-insurance to compliance use.

2. Market outcomes

• Oka established as category architect: Oka identified insurance as the answer to the TAB's double-counting condition, designed the commercial product, and bound the first live policies. Oka also worked directly with Verra and Gold Standard as they developed their CORSIA insurance frameworks, helping translate the mechanism into operational registry guidance. Gold Standard appointed Howden as a third-party policy assessor in 2025, and other insurers have since entered the category: signs of a healthy, growing market.
• Registry pathway formally established: Gold Standard and Verra now formally recognise the route Oka had operationalised. Project developers holding eligible LoAs can provide either evidence of a completed corresponding adjustment, or hold an approved insurance policy alongside a legal commitment to replace any double-counted credits. Corresponding Adjustment Protect is approved by both registries.
• Repeatable route that accelerates access: What began as a bespoke solution is now a market onramp for every eligible developer. Crucially, corresponding adjustments are reported once every two years, meaning the alternative route can delay sales by years. Insurance closes that gap, letting developers transact on issuance rather than waiting for the accounting cycle.

3. Environmental outcomes

Corresponding Adjustment Protect did not create the underlying emissions reductions. It helped support market access for credits generated by projects already delivering those reductions. DelAgua's broader programme-level impact includes:

• over 2 million clean cookstoves distributed;
• more than 9 million lives reached;
• 71% reduction in firewood use compared with traditional three-stone fires;
• more than 14 million tonnes of CO₂ prevented;
• protection of forest areas equivalent to ten times the size of London.

4. Co-benefit outcomes

DelAgua's clean cooking work supports household, health, and economic benefits, particularly for women and children. Reported programme-level benefits include reduced smoke exposure, lower wood use, improved household air quality, time savings from reduced fuelwood collection, and income opportunities through project operations and community health worker engagement. DelAgua reports 10,000+ project-based work opportunities, with 88% of participating Community Health Workers reporting improved financial stability.

"Working with Oka to develop a pioneering CORSIA insurance policy was a defining moment for DelAgua. It allowed us to convert our early Letters of Authorization into a credible, buyer-ready proposition at a time when the market had no established route for managing double counting risk. This policy enabled DelAgua to insure over 2.6 million credits of the 4.7 million credits we have brought to market so far. This set the commercial precedent that investors, registries and airlines needed to move forward with confidence. This partnership is a clear demonstration of how innovative industry partners can come together to build the infrastructure this market needs."

Euan McDougall, Chief Executive Officer, DelAgua