Isometric has released the draft Book and Claim Module for public consultation. The module sets out requirements for the issuance, tracking, and retirement of certificates where the environmental attribute is decoupled from the physical product—across low-carbon materials, sustainable fuels, energy, and beyond.
The module underpins Isometric's expansion into Environmental Attribute Certificates (EACs), announced in April, and will be followed by the release of sector-specific protocols, beginning with low-carbon materials.
Isometric is the only certifier to support carbon removal, superpollutant reduction, and EACs on a single platform and under one set of standards.
Book and claim explained
Low-carbon products—like green cement or sustainable aviation fuel—are rarely produced near demand, and transporting them long distances is neither practical nor efficient. Book and claim resolves this by separating the environmental attribute from the physical product. A buyer in one location can purchase a certificate tied to verified low-carbon production elsewhere, channeling revenue to the suppliers building the technologies that decarbonization depends on.
Demand for EACs is expanding. In the low-carbon materials space, Microsoft has signed EAC-based agreements with Fortera, Sublime, and Stegra; Meta has signed with Electra; and buyer alliances including the Sustainable Concrete Buyers Alliance (SCoBA) and the Sustainable Steel Buyers Platform (SSBP) have been established.
But the market lacks the certification infrastructure to support this growth. Rigorous certification ensures EACs represent real, additional, and traceable reductions, and cannot be double-counted.
The module
The Book and Claim Module sets universal requirements that apply across all categories of EACs, including sustainable fuels, low-carbon energy, and low-carbon materials. It ensures that every certificate issued is additional, tied to verified physical production, supported by an independently verified carbon intensity value, and protected against double counting:
- Suppliers must submit evidence that the product behind the claim has entered the supply chain.
- Market designation is fixed at the point of issuance and cannot be reclassified.
- Each certificate can only be retired once.
- Every step in the EAC lifecycle is publicly recorded on the Isometric Registry.
The module is the first framework for issuing, tracking, and retiring EACs that is fully compliant with the latest ISO 22095-3 Chain of Custody Standard and the forthcoming V2 of the SBTi Corporate Net Zero Standard.
This module was developed through collaboration between Isometric's in-house Science Team and reviewers from Isometric's independent Science Network of more than 400 academic experts.
Comments are welcome from buyers, suppliers, and scientists during the 30-day public consultation period ending on July 1, 2026.
Read more about Isometric's expansion into Environmental Attribute Certificates.
