The European Union’s Carbon Border Adjustment Mechanism (CBAM) is drawing attention to a vulnerability in international industrial supply chains. The concern is that manufacturers may not be able to substantiate emissions linked to steel or aluminium incorporated into finished products exported to the EU.
The issue can arise when metal is produced in one country, processed in another, and then exported to the EU as a covered or potentially covered product. Even if customs origin changes due to processing, relevant emissions information for covered precursor materials may still be required. Whether the finished article falls under CBAM depends on its Combined Nomenclature (CN) classification and the rules applicable to that product.
How definitive CBAM applies to embedded emissions
Under the definitive mechanism, which began operating in January 2026, an authorised EU declarant must calculate embedded emissions for goods within scope using the applicable methodology. Where actual emissions are used under the relevant rules, the figures must be supported by prescribed verification.
The European Commission publishes product- and country-specific default values for situations where their use is permitted under the legislation. Data requirements vary by product and production route, so a general corporate environmental statement cannot automatically replace an emissions calculation for a particular shipment.
As CBAM coverage could expand to downstream products, precursor traceability may become more important. For instance, a Turkish metal component made using Chinese steel could require a documented information chain connecting the EU importer, the component manufacturer, and the upstream steel mill, depending on final scope and accounting requirements.
Information sharing challenges across supply chains
Obtaining upstream information may be difficult when suppliers treat fuel consumption, production volumes, and emissions-allocation figures as commercially sensitive. Importers and manufacturers may therefore need arrangements that enable evidence to be shared securely with authorised verifiers. The goal is to avoid distributing confidential industrial data more widely than necessary.
In this context, documentation weaknesses can affect CBAM compliance. One risk is when a supplier identifies the company that fabricated a component but does not identify the installation that produced the steel or aluminium used in it. This can leave importers without upstream information needed under applicable rules.
A second gap involves calculating emissions at corporate-group level rather than for the specific installation and product. Where the methodology requires more detailed production data, group-wide figures may not provide an adequate basis for calculating embedded emissions.
Documentation gaps affecting emissions declarations
A third issue arises when reported material quantities do not reconcile with purchase records, production volumes, or invoices. Such discrepancies can undermine the credibility of emissions declarations. They can also create a risk that the same low-emission material is attributed to multiple products without adequate supporting records.
These weaknesses make consistency between production data, procurement documentation, and emissions calculations part of supply-chain control. The ability to connect material purchases with manufacturing processes and product quantities is therefore linked to substantiating emissions allocations.
Relevance for Serbia and regional exporters
The challenge is relevant for manufacturers in Serbia, Türkiye, and the Western Balkans that rely on internationally sourced metal feedstock. A Serbian processor exporting a product already covered by CBAM remains subject to applicable requirements regardless of whether its steel or aluminium originated in China or another third country.
At the same time, distinguishing between covered inputs and covered finished goods remains important. A product outside CBAM’s scope should not be treated as directly obligated solely because its metal input is covered. Any future liability would depend on product classification and legislation applicable at the relevant time.
For businesses operating across multiple jurisdictions, separating customs treatment of the finished article from information needed to establish emissions associated with covered materials becomes essential. This distinction affects what evidence must be available for CBAM-related calculations tied to precursor inputs.
Contract terms and internal coordination for upstream data
Supply agreements are expected to clarify which party provides upstream emissions information. They should also specify verification standards, retention periods for supporting evidence, and how corrected data will be transmitted to the authorised EU declarant.
Implementing these arrangements requires coordination across company functions. Quality assurance teams, accountants, customs specialists, and production engineers each hold parts of the information needed to connect material purchases, manufacturing processes, product quantities, and emissions calculations. No single function necessarily has complete visibility of the full chain.
Manufacturers able to trace metal from procurement through final production and substantiate emissions allocations under independent review may be better positioned to meet customer requirements. Companies unable to reconstruct relevant production history could face commercial disadvantages even if their manufacturing costs remain competitive.
As CBAM requirements develop, documenting and verifying precursor emissions is becoming an increasingly important element of industrial supply-chain management. For exporters, reliable traceability may support continued access to EU customers; for importers, gaps in upstream records can create compliance and commercial risk.