Clarity on Book & Claim nomenclature
Emissions from maritime transportation are among the heaviest contributors to global logistics, forming a major share of both upstream and downstream Scope 3 emissions that companies are required to report.
But unlike some sectors, ships can’t electrify overnight. Sustainable maritime fuels are emerging, but availability is still limited. And that’s where market‑based instruments like carbon credits, Environmental Attribute Certificates, and digital tokens come in.
While this methodology is gaining momentum, the lack of standardized approach has unintentionally created a terminology jungle. Different sectors, standards, and companies have introduced their own labels - often describing the same type of environmental attribute, but with their own branding or legacy language.
This adds unnecessary complexity to something that should be easy to understand.
In this article we explore some of the most common naming variations used for EAC‑like instruments today:
How does Book & Claim and EACs abate supply chain emisisons?
What EACs Are Called Across the Market
Environmental Attribute Certificate (EAC)
An umbrella term covering all instruments that document, transfer, and enable claims on environmental benefits, regardless of sector, fuel type, or registry design.
In the energy sector, EACs are a well‑established concept used to allocate renewable and low‑carbon attributes (such as Guarantees of Origin or RECs) independently from physical energy flows. This logic is increasingly reflected in SBTi’s ongoing work, which signals growing acceptance of book‑and‑claim approaches as a credible mechanism for addressing Scope 3 emissions reductions, particularly in hard‑to‑abate sectors like transport.
BCU (Book & Claim Unit)
A generic term used to describe a unit created under a book‑and‑claim system, representing a verified environmental attribute that can be allocated independently from the physical flow of goods or fuels.
Tokens
Often digital or blockchain‑enabled representations.
A digital representation of environmental attributes — often used in registries or blockchain‑based systems — designed to enhance traceability, transferability, and auditability of emissions data.
LETS (Low Emission Transport Service units)
The terminology used within Smart Freight Centre’s Market‑Based Measures framework to describe units that allocate the emissions benefits of low‑emission transport services to cargo owners and other value‑chain actors.
ISCC Credit
A unit issued under the ISCC certification framework, used to allocate sustainability attributes (such as renewable fuel use or emissions reductions) through mass‑balance or book‑and‑claim approaches..
Carbon Credit
The broadest and most widely recognised term, typically referring to a unit representing one tonne of CO₂e avoided or removed, and often used as an umbrella label even when underlying methodologies differ.
TIEC (Transferable Instrument with Entitlement to Claim)
A formalised term introduced in ISO/DIS 13659 to define transferable instruments used in chain‑of‑custody and book‑and‑claim systems, explicitly linking the instrument to a clear, auditable right to make an emissions‑related claim.
All of these serve the same fundamental purpose: they document and allocate the “unit value” created by a verified low‑carbon activity, such as using sustainable fuel or reducing emissions through a specific intervention.
Despite the variety of names, the underlying mechanics, intent, and climate impact logic are aligned. The differences are mostly in branding, methodology origin, or sector preference — not in purpose.
The Same Is True for Book‑and‑Claim Operations
The inconsistency doesn’t stop at what we call the certificates. Even the actions within book & claim vary across the industry. What one organization refers to as a “booking”, another describes as a “registration” - and so on.
Here are the common operations and their naming variations:
1. Booking (Creating or registering the environmental attribute)
Often also referred to as:
Registering
Issuing
Allocating
Generating
Crediting
Recording
All of these refer to the moment when an environmental benefit (e.g., use of SAF or SMF) is verified and turned into a transferable unit in the system.
2. Transfer (Moving the attribute between parties)
Sometimes called:
Trading
Hand‑over
Reassigning
Forwarding
Selling
Allocations
This step simply reflects the movement of the certificate/EAC from one party in the supply chain to another.
3. Claiming (Using the unit to make an emissions claim)
Often described in different ways, such as:
Retiring
Redeeming
Applying
Using
Attributing
Reporting
This step refer always to the same action: the holder uses the unit to support an emissions‑related claim in their reporting.
Wrapping up - Why Clarity Matters?
All these variations — in both naming the certificates and naming the actions — can make the space feel fragmented and confusing. And confusion leads to hesitation, slows adoption, and undermines trust.
But when we cut through the noise, we see something simple:
Regardless of what different players call them, EACs follow the same structure and the same logic. They recognize an environmental benefit, track it, transfer it, and allow someone to claim it with integrity.
Hoping that this can help all of you finding more clarity - and feel more safe - when approaching the Book & Claim world.
Questions? Feel free to reach us out at info@katalist.org in case you are still in doubt or struggle with understanding how can your company benefits from using Book & Claim to decarbonize its supply chain.