One page, one name in the Scope 1 field
The RSB Book & Claim Registry issued a one-page retirement statement on 6 May 2026, and the name in its Scope 1 field is Delta Air Lines Inc.
In May 2026, environmental attributes linked to 36 tonnes of sustainable aviation fuel made from Technical Corn Oil, with lifecycle emissions 80.7% below the fossil baseline, were retired on the RSB Book & Claim Registry. Delta Air Lines took the Scope 1 claim, and Future Energy Global used the separately allocated Scope 3 attributes against its calculated 2025 business-travel emissions.
A retirement record like that is the end point of a Scope 1 purchase. The rest of this page follows the route to it, so you know what to ask for and what to check before your own name goes in that field.
What you are buying
Book and Claim separates the environmental attributes of a certified batch of sustainable aviation fuel (SAF) from the fuel itself. The fuel goes into supply wherever it was blended, while the attributes move through a registry to whoever buys them. That is how you can claim a reduction from a batch your own aircraft never uplifted.
Each batch has two claims attached. The Scope 1 claim belongs to the airline named when the units are retired, and to no one else. The Scope 3 attributes from the same batch can go to companies that buy them for reporting on business travel or freight, subject to the reporting standard they use, and their demand helps share the cost of the batch. Why that is not double counting has its own lesson.
Five steps from contract to retirement
- Agree in writing that the purchase includes the Scope 1 claim, and on which registry the units sit. Scope 3 attributes alone give an airline no Scope 1 claim to retire. Ask for the certification behind the batch too, because the statement will print it and your auditor will read it.
- Open an account on that registry. Registries in use for SAF include the RSB Book & Claim Registry, the ISCC Credit Transfer System, IATA’s CADO SAF Registry, the SAFc Registry, and the Assure SAF Registry. Units differ in size between them. On the RSB registry one unit is a tonne of neat certified SAF; on the CADO SAF Registry it is a kilogram.
- The producer or blender named on the batch’s proof of sustainability usually registers it, and the document is checked before any units become active. On the CADO SAF Registry that check is done by the registry’s own validators, who also ask partner registries whether the same batch is already registered with them.
- The seller transfers the units to your account.
- You retire them for your Scope 1 claim. Retirement takes the units out of circulation for good, so they cannot be transferred or reinstated afterwards. The registry then records the retirement in your name. The RSB registry issues a retirement statement, and both the RSB and CADO registries list retirements in public tables that anyone can read.
What the statement tells your auditor
The retirement statement is the evidence for your claim. On the RSB registry it records the Scope 1 holder, the certification, the feedstock and production pathway, the lifecycle emissions value against a fossil baseline, the type of reporting, and any incentives claimed for the fuel. Our registries lesson reads a real one, field by field.
The RSB adds a note at the foot of the page: the parties named should take their own advice on how the claim applies legally, in their accounts, and under any regulation. What the statement shows is that the attributes were retired once, to the parties named on it.
How the claim sits in your report
In the RSB’s worked example of Book and Claim accounting, published in June 2026, the airline keeps two figures apart. The emissions from the fuel it actually burned stay in its greenhouse gas inventory, calculated from real fuel use, while the reduction supported by Book and Claim is disclosed separately. It does not adjust the inventory.
The size of the reduction depends on the verified lifecycle data for that batch, so use the figure on your own statement rather than an average. The RSB makes the point on purpose: in its example, the upstream part of the airline’s reduction comes out negative for the pathway chosen.
How you report it depends on your target and the standard you report against. The GHG Protocol is still developing its guidance on market instruments, and the RSB says its example is not a normative standard or official accounting guidance.
Voluntary claims and compliance claims
Compliance schemes set their own rules on which fuel counts and how it must be documented, and a registry record does not settle that question by itself. The CADO SAF Registry, for example, asks at redemption whether a claim is voluntary or for CORSIA, ICAO’s scheme for international aviation, and accepts a CORSIA claim only for fuel certified to CORSIA. Your verifier and the state authority you report to decide whether a claim counts, and the choice made at redemption cannot be changed afterwards. Check with them before you retire anything you mean to use for compliance.
The Delta retirement above was recorded as voluntary reporting, and our work with airlines is on voluntary purchases.
Where we fit
We do not produce fuel. We buy certified attributes from producers and suppliers and settle each batch on the registry where it is registered. We have transacted on all five of the registries named above.
We are certified by RSB and ISCC, and independently audited each year. When an airline takes the Scope 1 claim, we can place the Scope 3 attributes from the same batch with corporate buyers. Our page for airlines shows how the two sides of a batch work together.